Slack Alert it's not working

I set an alert to be sent to a public slack channel when it has results and it's not working

Hi @Mori
Post "Diagnostic Info" from Admin > Troubleshooting.
Check your logs around the time, when you expected to see an alert - Admin > Troubleshooting > Logs.

{
"browser-info": {
"language": "en",
"platform": "MacIntel",
"userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/100.0.4896.127 Safari/537.36",
"vendor": "Google Inc."
},
"system-info": {
"file.encoding": "UTF-8",
"java.runtime.name": "OpenJDK Runtime Environment",
"java.runtime.version": "11.0.15+10",
"java.vendor": "Eclipse Adoptium",
"java.vendor.url": "https://adoptium.net/",
"java.version": "11.0.15",
"java.vm.name": "OpenJDK 64-Bit Server VM",
"java.vm.version": "11.0.15+10",
"os.name": "Linux",
"os.version": "4.9.0-11-amd64",
"user.language": "en",
"user.timezone": "UTC"
},
"metabase-info": {
"databases": [
"postgres",
"redshift",
"h2"
],
"hosting-env": "unknown",
"application-database": "postgres",
"application-database-details": {
"database": {
"name": "PostgreSQL",
"version": "10.18"
},
"jdbc-driver": {
"name": "PostgreSQL JDBC Driver",
"version": "42.3.2"
}
},
"run-mode": "prod",
"version": {
"date": "2022-05-02",
"tag": "v0.43.0",
"branch": "release-x.43.x",
"hash": "ee686fc"
},
"settings": {
"report-timezone": "America/Buenos_Aires"
}
}
}

Logs:
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.analyze fingerprint-fields Analyzed [···································] 30% Table 3,237 'public.monthly_payment_relationships'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.util FINISHED: step 'fingerprint-fields' for postgres Database 10 'Card API PRODU (!)' (6.5 s)
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.util STARTING: step 'classify-fields' for postgres Database 10 'Card API PRODU (!)'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.analyze classify-fields Analyzed [
······························] 40% Table 2,294 'dominicana.bank_office_aliases'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.analyze classify-fields Analyzed [·························] 50% Table 2,332 'pglogical.tables'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.analyze classify-fields Analyzed [
····················] 60% Table 2,723 'uruguay.authorization_letters'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.util FINISHED: step 'classify-fields' for postgres Database 10 'Card API PRODU (!)' (412.1 ms)
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.util STARTING: step 'classify-tables' for postgres Database 10 'Card API PRODU (!)'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.analyze classify-tables Analyzed [******************************···············] 70% Table 2,302 'argentina.movements_legacy'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:18-03:00 INFO metabase.sync.analyze classify-tables Analyzed [··········] 80% Table 2,376 'argentina.credentials'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:19-03:00 INFO metabase.sync.analyze classify-tables Analyzed [
·····] 90% Table 2,244 'dominicana.payments'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:19-03:00 INFO metabase.sync.util FINISHED: step 'classify-tables' for postgres Database 10 'Card API PRODU (!)' (382.9 ms)
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:19-03:00 INFO metabase.sync.util FINISHED: Analyze data for postgres Database 10 'Card API PRODU (!)' (7.3 s)
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:19-03:00 DEBUG metabase.server.middleware.log POST /api/dataset 202 [ASYNC: completed] 118.5 ms (42 DB calls) App DB connections: 1/15 Jetty threads: 2/50 (5 idle, 0 queued) (142 total active threads) Queries in flight: 0 (0 queued); postgres DB 12 connections: 0/1 (0 threads blocked)

@Mori There's no log that alerts are being executed. Try setting the Alert to hourly, so you can see in the log more details.

[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:00-03:00 WARN metabase.integrations.slack {:error-code "not_in_channel",
:message "Slack API error: not_in_channel",
:response {:ok false, :error "not_in_channel"}}

[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:00-03:00 WARN metabase.integrations.slack {:error-code "channel_not_found",
:message "Slack API error: channel_not_found",
:response {:ok false, :error "channel_not_found"}}

[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-11T18:00:00-03:00 ERROR metabase.pulse Error sending notification!
clojure.lang.ExceptionInfo: Slack API error: channel_not_found {:error-code "channel_not_found", :message "Slack API error: channel_not_found", :response {:ok false, :error "channel_not_found"}, :url "https://slack.com/api/conversations.join", :request {:headers {:authorization "Bearer\nxoxb"}, :as :stream, :conn-timeout 10000, :socket-timeout 10000, :form-params {:channel "metabase-bot"}}}
at metabase.integrations.slack$do_slack_request.invokeStatic(slack.clj:125)
at metabase.integrations.slack$do_slack_request.invoke(slack.clj:106)
at metabase.integrations.slack$POST.invokeStatic(slack.clj:135)
at metabase.integrations.slack$POST.invoke(slack.clj:132)
at metabase.integrations.slack$fn__63305$join_channel_BANG___63310$fn__63311.invoke(slack.clj:267)
at metabase.integrations.slack$fn__63305$join_channel_BANG___63310.invoke(slack.clj:263)
at metabase.integrations.slack$fn__63330$upload_file_BANG___63335$fn__63336$fn__63337.invoke(slack.clj:282)
at metabase.integrations.slack$fn__63330$upload_file_BANG___63335$fn__63336.invoke(slack.clj:276)
at metabase.integrations.slack$fn__63330$upload_file_BANG___63335.invoke(slack.clj:269)
at metabase.pulse$create_and_upload_slack_attachments_BANG_$fn__76265.invoke(pulse.clj:202)
at clojure.core.protocols$fn__8181.invokeStatic(protocols.clj:168)
at clojure.core.protocols$fn__8181.invoke(protocols.clj:124)
at clojure.core.protocols$fn__8136$G__8131__8145.invoke(protocols.clj:19)
at clojure.core.protocols$seq_reduce.invokeStatic(protocols.clj:31)
at clojure.core.protocols$fn__8166.invokeStatic(protocols.clj:75)
at clojure.core.protocols$fn__8166.invoke(protocols.clj:75)
at clojure.core.protocols$fn__8110$G__8105__8123.invoke(protocols.clj:13)
at clojure.core$reduce.invokeStatic(core.clj:6830)
at clojure.core$reduce.invoke(core.clj:6812)
at metabase.pulse$create_and_upload_slack_attachments_BANG_.invokeStatic(pulse.clj:195)
at metabase.pulse$create_and_upload_slack_attachments_BANG_.invoke(pulse.clj:186)
at metabase.pulse$create_and_upload_slack_attachments_BANG_.invokeStatic(pulse.clj:192)
at metabase.pulse$create_and_upload_slack_attachments_BANG_.invoke(pulse.clj:186)
at metabase.pulse$fn__76378.invokeStatic(pulse.clj:375)
at metabase.pulse$fn__76378.invoke(pulse.clj:373)
at clojure.lang.MultiFn.invoke(MultiFn.java:229)
at metabase.pulse$send_notifications_BANG_$fn__76393.invoke(pulse.clj:391)
at metabase.pulse$send_notifications_BANG_.invokeStatic(pulse.clj:390)
at metabase.pulse$send_notifications_BANG_.invoke(pulse.clj:386)
at metabase.pulse$send_pulse_BANG_.invokeStatic(pulse.clj:415)
at metabase.pulse$send_pulse_BANG_.doInvoke(pulse.clj:395)
at clojure.lang.RestFn.invoke(RestFn.java:439)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80711$fn__80729$fn__80730.invoke(send_pulses.clj:55)
at metabase.models.task_history$fn__41374$do_with_task_history__41379$fn__41380.invoke(task_history.clj:88)
at metabase.models.task_history$fn__41374$do_with_task_history__41379.invoke(task_history.clj:83)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80711$fn__80729.invoke(send_pulses.clj:52)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80711.invoke(send_pulses.clj:51)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708.invoke(send_pulses.clj:38)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80709.invoke(send_pulses.clj:45)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708.invoke(send_pulses.clj:38)
at metabase.task.send_pulses.SendPulses$fn__80765.invoke(send_pulses.clj:96)
at metabase.models.task_history$fn__41374$do_with_task_history__41379$fn__41380.invoke(task_history.clj:88)
at metabase.models.task_history$fn__41374$do_with_task_history__41379.invoke(task_history.clj:83)
at metabase.task.send_pulses.SendPulses.execute(send_pulses.clj:82)
at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:573)
Caused by: clojure.lang.ExceptionInfo: Slack API error: channel_not_found {:error-code "channel_not_found", :message "Slack API error: channel_not_found", :response {:ok false, :error "channel_not_found"}}
at metabase.integrations.slack$handle_error.invokeStatic(slack.clj:97)
at metabase.integrations.slack$handle_error.invoke(slack.clj:77)
at metabase.integrations.slack$handle_response.invokeStatic(slack.clj:104)
at metabase.integrations.slack$handle_response.invoke(slack.clj:99)
at metabase.integrations.slack$do_slack_request.invokeStatic(slack.clj:123)
... 45 more

@Mori It says channel not found for metabase-bot, so I'm guessing that you have not created that channel, but that is the channel you have configured to send the files to.
Try removing your Slack configuration and do it again:
https://www.metabase.com/docs/latest/administration-guide/09-setting-up-slack.html

I remove Slack and do the configuration again! I set up an alert for 10 am Argentina time I will keep you informed!!

Still not working!!

[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:00-03:00 WARN metabase.integrations.slack {:error-code "not_in_channel",
:message "Slack API error: not_in_channel",
:response {:ok false, :error "not_in_channel"}}

[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:00-03:00 WARN metabase.integrations.slack {:error-code "channel_not_found",
:message "Slack API error: channel_not_found",
:response {:ok false, :error "channel_not_found"}}

[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:00-03:00 ERROR metabase.pulse Error sending notification!
clojure.lang.ExceptionInfo: Slack API error: channel_not_found {:error-code "channel_not_found", :message "Slack API error: channel_not_found", :response {:ok false, :error "channel_not_found"}, :url "https://slack.com/api/conversations.join", :request {:headers {:authorization "Bearer\nxoxb-2970845841-3518458392596-rtkT7hqYt5QnLkvJ2NB1svRW"}, :as :stream, :conn-timeout 10000, :socket-timeout 10000, :form-params {:channel "metabase-bot"}}}
at metabase.integrations.slack$do_slack_request.invokeStatic(slack.clj:125)
at metabase.integrations.slack$do_slack_request.invoke(slack.clj:106)
at metabase.integrations.slack$POST.invokeStatic(slack.clj:135)
at metabase.integrations.slack$POST.invoke(slack.clj:132)
at metabase.integrations.slack$fn__63305$join_channel_BANG___63310$fn__63311.invoke(slack.clj:267)
at metabase.integrations.slack$fn__63305$join_channel_BANG___63310.invoke(slack.clj:263)
at metabase.integrations.slack$fn__63330$upload_file_BANG___63335$fn__63336$fn__63337.invoke(slack.clj:282)
at metabase.integrations.slack$fn__63330$upload_file_BANG___63335$fn__63336.invoke(slack.clj:276)
at metabase.integrations.slack$fn__63330$upload_file_BANG___63335.invoke(slack.clj:269)
at metabase.pulse$create_and_upload_slack_attachments_BANG_$fn__76265.invoke(pulse.clj:202)
at clojure.core.protocols$fn__8181.invokeStatic(protocols.clj:168)
at clojure.core.protocols$fn__8181.invoke(protocols.clj:124)
at clojure.core.protocols$fn__8136$G__8131__8145.invoke(protocols.clj:19)
at clojure.core.protocols$seq_reduce.invokeStatic(protocols.clj:31)
at clojure.core.protocols$fn__8166.invokeStatic(protocols.clj:75)
at clojure.core.protocols$fn__8166.invoke(protocols.clj:75)
at clojure.core.protocols$fn__8110$G__8105__8123.invoke(protocols.clj:13)
at clojure.core$reduce.invokeStatic(core.clj:6830)
at clojure.core$reduce.invoke(core.clj:6812)
at metabase.pulse$create_and_upload_slack_attachments_BANG_.invokeStatic(pulse.clj:195)
at metabase.pulse$create_and_upload_slack_attachments_BANG_.invoke(pulse.clj:186)
at metabase.pulse$create_and_upload_slack_attachments_BANG_.invokeStatic(pulse.clj:192)
at metabase.pulse$create_and_upload_slack_attachments_BANG_.invoke(pulse.clj:186)
at metabase.pulse$fn__76378.invokeStatic(pulse.clj:375)
at metabase.pulse$fn__76378.invoke(pulse.clj:373)
at clojure.lang.MultiFn.invoke(MultiFn.java:229)
at metabase.pulse$send_notifications_BANG_$fn__76393.invoke(pulse.clj:391)
at metabase.pulse$send_notifications_BANG_.invokeStatic(pulse.clj:390)
at metabase.pulse$send_notifications_BANG_.invoke(pulse.clj:386)
at metabase.pulse$send_pulse_BANG_.invokeStatic(pulse.clj:415)
at metabase.pulse$send_pulse_BANG_.doInvoke(pulse.clj:395)
at clojure.lang.RestFn.invoke(RestFn.java:439)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80711$fn__80729$fn__80730.invoke(send_pulses.clj:55)
at metabase.models.task_history$fn__41374$do_with_task_history__41379$fn__41380.invoke(task_history.clj:88)
at metabase.models.task_history$fn__41374$do_with_task_history__41379.invoke(task_history.clj:83)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80711$fn__80729.invoke(send_pulses.clj:52)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80711.invoke(send_pulses.clj:51)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708.invoke(send_pulses.clj:38)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80709.invoke(send_pulses.clj:45)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708.invoke(send_pulses.clj:38)
at metabase.task.send_pulses.SendPulses$fn__80765.invoke(send_pulses.clj:96)
at metabase.models.task_history$fn__41374$do_with_task_history__41379$fn__41380.invoke(task_history.clj:88)
at metabase.models.task_history$fn__41374$do_with_task_history__41379.invoke(task_history.clj:83)
at metabase.task.send_pulses.SendPulses.execute(send_pulses.clj:82)
at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:573)
Caused by: clojure.lang.ExceptionInfo: Slack API error: channel_not_found {:error-code "channel_not_found", :message "Slack API error: channel_not_found", :response {:ok false, :error "channel_not_found"}}
at metabase.integrations.slack$handle_error.invokeStatic(slack.clj:97)
at metabase.integrations.slack$handle_error.invoke(slack.clj:77)
at metabase.integrations.slack$handle_response.invokeStatic(slack.clj:104)
at metabase.integrations.slack$handle_response.invoke(slack.clj:99)
at metabase.integrations.slack$do_slack_request.invokeStatic(slack.clj:123)
... 45 more
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:04-03:00 INFO metabase.sync.util FINISHED: step 'sync-tables' for postgres Database 10 'Card API PRODU (!)' (3.8 s)
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:04-03:00 INFO metabase.sync.util STARTING: step 'sync-fields' for postgres Database 10 'Card API PRODU (!)'
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:05-03:00 WARN metabase.models.field Invalid Field :semantic_type :type/Number: falling back to null
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:05-03:00 WARN metabase.models.field Invalid Field :semantic_type :type/Number: falling back to null
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:05-03:00 WARN metabase.models.field Invalid Field :semantic_type :type/Number: falling back to null
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:05-03:00 WARN metabase.models.field Invalid Field :semantic_type :type/Number: falling back to null
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:05-03:00 WARN metabase.models.field Invalid Field :semantic_type :type/Number: falling back to null
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:05-03:00 WARN metabase.models.field Invalid Field :semantic_type :type/Number: falling back to null
[9616fefd-63d8-467c-9e25-2a7b7752ea64] 2022-05-12T15:00:05-03:00 ERROR metabase.task.send-pulses Error sending Pulse 5
clojure.lang.ExceptionInfo: Unable to compare results to goal for alert. {:pulse #metabase.models.pulse.PulseInstance{:archived false, :collection_position nil, :creator #metabase.models.user.UserInstance{:email "joaquin.suarez@increase.app", :first_name "Joaquin", :last_login #t "2020-11-16T18:37:53.168055Z", :is_qbnewb false, :is_superuser true, :id 1, :last_name "Suarez Bodean", :date_joined #t "2019-03-21T17:49:33.088Z", :common_name "Joaquin Suarez Bodean"}, :channels (#metabase.models.pulse_channel.PulseChannelInstance{:schedule_type :hourly, :schedule_hour nil, :channel_type :email, :schedule_frame nil, :recipients (), :updated_at #t "2019-05-29T20:37:12.275Z", :details {:emails nil}, :pulse_id 5, :id 6, :schedule_day nil, :enabled true, :created_at #t "2019-05-29T20:37:12.275Z"} #metabase.models.pulse_channel.PulseChannelInstance{:schedule_type :hourly, :schedule_hour nil, :channel_type :slack, :schedule_frame nil, :recipients (), :updated_at #t "2019-05-29T20:37:12.281Z", :details {:channel "@lucia"}, :pulse_id 5, :id 7, :schedule_day nil, :enabled true, :created_at #t "2019-05-29T20:37:12.281Z"}), :alert_condition "goal", :collection_id nil, :name nil, :creator_id 1, :updated_at #t "2019-05-29T20:37:12.259Z", :alert_first_only true, :channel-ids (6 7), :id 5, :cards (), :skip_if_empty true, :parameters (), :dashboard_id nil, :created_at #t "2019-05-29T20:37:12.259Z", :alert_above_goal true}, :result nil}
at metabase.pulse$goal_met_QMARK_.invokeStatic(pulse.clj:231)
at metabase.pulse$goal_met_QMARK_.invoke(pulse.clj:224)
at metabase.pulse$fn__76291.invokeStatic(pulse.clj:260)
at metabase.pulse$fn__76291.invoke(pulse.clj:253)
at clojure.lang.MultiFn.invoke(MultiFn.java:234)
at metabase.pulse$results__GT_notifications.invokeStatic(pulse.clj:339)
at metabase.pulse$results__GT_notifications.invoke(pulse.clj:337)
at metabase.pulse$pulse__GT_notifications.invokeStatic(pulse.clj:350)
at metabase.pulse$pulse__GT_notifications.invoke(pulse.clj:347)
at metabase.pulse$send_pulse_BANG_.invokeStatic(pulse.clj:415)
at metabase.pulse$send_pulse_BANG_.doInvoke(pulse.clj:395)
at clojure.lang.RestFn.invoke(RestFn.java:439)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80711$fn__80729$fn__80730.invoke(send_pulses.clj:55)
at metabase.models.task_history$fn__41374$do_with_task_history__41379$fn__41380.invoke(task_history.clj:88)
at metabase.models.task_history$fn__41374$do_with_task_history__41379.invoke(task_history.clj:83)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80711$fn__80729.invoke(send_pulses.clj:52)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80711.invoke(send_pulses.clj:51)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708.invoke(send_pulses.clj:38)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708$fn__80709.invoke(send_pulses.clj:45)
at metabase.task.send_pulses$fn__80699$send_pulses_BANG___80708.invoke(send_pulses.clj:38)
at metabase.task.send_pulses.SendPulses$fn__80765.invoke(send_pulses.clj:96)
at metabase.models.task_history$fn__41374$do_with_task_history__41379$fn__41380.invoke(task_history.clj:88)
at metabase.models.task_history$fn__41374$do_with_task_history__41379.invoke(task_history.clj:83)
at metabase.task.send_pulses.SendPulses.execute(send_pulses.clj:82)
at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:573)

@Mori

It's saying that the channel metabase-bot still does not exist.
And it is also having problems with sending the alert: Unable to compare results to goal for alert

@flamber we are experiencing the same issue.

Diagnostic info:

{
  "browser-info": {
    "language": "en-GB",
    "platform": "MacIntel",
    "userAgent": "Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/103.0.0.0 Safari/537.36",
    "vendor": "Google Inc."
  },
  "system-info": {
    "file.encoding": "UTF-8",
    "java.runtime.name": "OpenJDK Runtime Environment",
    "java.runtime.version": "11.0.15+10",
    "java.vendor": "Eclipse Adoptium",
    "java.vendor.url": "https://adoptium.net/",
    "java.version": "11.0.15",
    "java.vm.name": "OpenJDK 64-Bit Server VM",
    "java.vm.version": "11.0.15+10",
    "os.name": "Linux",
    "os.version": "4.14.276-211.499.amzn2.x86_64",
    "user.language": "en",
    "user.timezone": "GMT"
  },
  "metabase-info": {
    "databases": [
      "bigquery-cloud-sdk",
      "postgres"
    ],
    "hosting-env": "unknown",
    "application-database": "postgres",
    "application-database-details": {
      "database": {
        "name": "PostgreSQL",
        "version": "13.4"
      },
      "jdbc-driver": {
        "name": "PostgreSQL JDBC Driver",
        "version": "42.3.2"
      }
    },
    "run-mode": "prod",
    "version": {
      "date": "2022-06-13",
      "tag": "v0.43.3",
      "branch": "release-x.43.x",
      "hash": "c9c7ef0"
    },
    "settings": {
      "report-timezone": "Europe/Copenhagen"
    }
  }

Logs:

[0a57a325-8c8c-4bbf-8845-270c08d368de] 2022-06-27T15:00:00+02:00 INFO metabase.task.send-pulses Sending scheduled pulses...
    [0a57a325-8c8c-4bbf-8845-270c08d368de] 2022-06-27T15:00:13+02:00 WARN metabase.integrations.slack {:error-code "not_in_channel",
     :message "Slack API error: not_in_channel",
     :response {:ok false, :error "not_in_channel"}}

[0a57a325-8c8c-4bbf-8845-270c08d368de] 2022-06-27T15:00:13+02:00 WARN metabase.integrations.slack {:error-code "channel_not_found",
 :message "Slack API error: channel_not_found",
 :response {:ok false, :error "channel_not_found"}}

[0a57a325-8c8c-4bbf-8845-270c08d368de] 2022-06-27T15:00:13+02:00 ERROR metabase.pulse Error sending notification!
clojure.lang.ExceptionInfo: Slack API error: channel_not_found {:error-code "channel_not_found", :message "Slack API error: channel_not_found", :response {:ok false, :error "channel_not_found"}, :url "https://slack.com/api/conversations.join", :request {:headers {:authorization "Bearer\nxoxb-1668506773634-3709298978311-Slq5PK564DCtvK2PeR2sdl9G"}, :as :stream, :conn-timeout 10000, :socket-timeout 10000, :form-params {:channel "metabase_files"}}}
	at metabase.integrations.slack$do_slack_request.invokeStatic(slack.clj:125)
	at metabase.integrations.slack$do_slack_request.invoke(slack.clj:106)
	at metabase.integrations.slack$POST.invokeStatic(slack.clj:135)
	at metabase.integrations.slack$POST.invoke(slack.clj:132)
	at metabase.integrations.slack$fn__63402$join_channel_BANG___63407$fn__63408.invoke(slack.clj:273)
	at metabase.integrations.slack$fn__63402$join_channel_BANG___63407.invoke(slack.clj:269)
	at metabase.integrations.slack$fn__63427$upload_file_BANG___63432$fn__63433$fn__63434.invoke(slack.clj:288)
	at metabase.integrations.slack$fn__63427$upload_file_BANG___63432$fn__63433.invoke(slack.clj:282)
	at metabase.integrations.slack$fn__63427$upload_file_BANG___63432.invoke(slack.clj:275)
	at metabase.pulse$create_and_upload_slack_attachments_BANG_$fn__76392.invoke(pulse.clj:202)
	at clojure.core.protocols$fn__8181.invokeStatic(protocols.clj:168)
	at clojure.core.protocols$fn__8181.invoke(protocols.clj:124)
	at clojure.core.protocols$fn__8136$G__8131__8145.invoke(protocols.clj:19)
	at clojure.core.protocols$seq_reduce.invokeStatic(protocols.clj:31)
	at clojure.core.protocols$fn__8166.invokeStatic(protocols.clj:75)
	at clojure.core.protocols$fn__8166.invoke(protocols.clj:75)
	at clojure.core.protocols$fn__8110$G__8105__8123.invoke(protocols.clj:13)
	at clojure.core$reduce.invokeStatic(core.clj:6830)
	at clojure.core$reduce.invoke(core.clj:6812)
	at metabase.pulse$create_and_upload_slack_attachments_BANG_.invokeStatic(pulse.clj:195)
	at metabase.pulse$create_and_upload_slack_attachments_BANG_.invoke(pulse.clj:186)
	at metabase.pulse$create_and_upload_slack_attachments_BANG_.invokeStatic(pulse.clj:192)
	at metabase.pulse$create_and_upload_slack_attachments_BANG_.invoke(pulse.clj:186)
	at metabase.pulse$fn__76505.invokeStatic(pulse.clj:375)
	at metabase.pulse$fn__76505.invoke(pulse.clj:373)
	at clojure.lang.MultiFn.invoke(MultiFn.java:229)
	at metabase.pulse$send_notifications_BANG_$fn__76520.invoke(pulse.clj:391)
	at metabase.pulse$send_notifications_BANG_.invokeStatic(pulse.clj:390)
	at metabase.pulse$send_notifications_BANG_.invoke(pulse.clj:386)
	at metabase.pulse$send_pulse_BANG_.invokeStatic(pulse.clj:415)
	at metabase.pulse$send_pulse_BANG_.doInvoke(pulse.clj:395)
	at clojure.lang.RestFn.invoke(RestFn.java:439)
	at metabase.task.send_pulses$fn__80828$send_pulses_BANG___80837$fn__80840$fn__80858$fn__80859.invoke(send_pulses.clj:55)
	at metabase.models.task_history$fn__41394$do_with_task_history__41399$fn__41400.invoke(task_history.clj:88)
	at metabase.models.task_history$fn__41394$do_with_task_history__41399.invoke(task_history.clj:83)
	at metabase.task.send_pulses$fn__80828$send_pulses_BANG___80837$fn__80840$fn__80858.invoke(send_pulses.clj:52)
	at metabase.task.send_pulses$fn__80828$send_pulses_BANG___80837$fn__80840.invoke(send_pulses.clj:51)
	at metabase.task.send_pulses$fn__80828$send_pulses_BANG___80837.invoke(send_pulses.clj:38)
	at metabase.task.send_pulses$fn__80828$send_pulses_BANG___80837$fn__80838.invoke(send_pulses.clj:45)
	at metabase.task.send_pulses$fn__80828$send_pulses_BANG___80837.invoke(send_pulses.clj:38)
	at metabase.task.send_pulses.SendPulses$fn__80894.invoke(send_pulses.clj:96)
	at metabase.models.task_history$fn__41394$do_with_task_history__41399$fn__41400.invoke(task_history.clj:88)
	at metabase.models.task_history$fn__41394$do_with_task_history__41399.invoke(task_history.clj:83)
	at metabase.task.send_pulses.SendPulses.execute(send_pulses.clj:82)
	at org.quartz.core.JobRunShell.run(JobRunShell.java:202)
	at org.quartz.simpl.SimpleThreadPool$WorkerThread.run(SimpleThreadPool.java:573)
Caused by: clojure.lang.ExceptionInfo: Slack API error: channel_not_found {:error-code "channel_not_found", :message "Slack API error: channel_not_found", :response {:ok false, :error "channel_not_found"}}
	at metabase.integrations.slack$handle_error.invokeStatic(slack.clj:97)
	at metabase.integrations.slack$handle_error.invoke(slack.clj:77)
	at metabase.integrations.slack$handle_response.invokeStatic(slack.clj:104)
	at metabase.integrations.slack$handle_response.invoke(slack.clj:99)
	at metabase.integrations.slack$do_slack_request.invokeStatic(slack.clj:123)
	... 45 more
    }

Notes:
We are not sending any pulses to a channel called 'metabase_files'.

We have this issue for two alerts now. Both of them trigger fine with sending emails, but nothing is sent to slack. Slack alerts are working fine for other questions.

We have tried removing the Slack integration and installing it again, but without any luck.

@trinefn The files channel is needed to store the attachments. It's not for humans. There has to be a files channel, and you need to manually add the App to that channel.
Read more here: https://github.com/metabase/metabase/issues/23229 and https://github.com/metabase/metabase/issues/20936

thanks @flamber! :pray:
The workaround mentioned by noahmoss in https://github.com/metabase/metabase/issues/23229 fixed the issue