Slack Integration - Images Not Sending to Private Channels

We are experiencing an issue with our Metabase and Slack integration, specifically related to sending alerts to private channels.

We have set up a Metabase to send alerts to Slack, and for this purpose, we have designated a channel to receive these images. The public channel has been verified and is receiving everything as expected. However, since this morning, images are not being sent to private channels configured to receive alerts.

We rely on these alerts for our workflow, and it's crucial for us to have this functionality working correctly.
Could you please help us to investigate this issue?
We have Metabase version v1.49.14 and we are using the cloud.

Thank you for your assistance.

If you're a paid customer please reach out via help@metabase.com to submit a ticket.

you need to invite the user to those private channels

Thanks for your answers, just sharing here in case anyone else runs into same issue.
The private channel already has the Metabase app invited. We receive Metabase alerts into these private channels. The issue is that these alerts do not have the image included in the message, so the alerts are empty and they should not be.

I am also seeing this issue with Slack Integration, which seemed to start at around 10pm BST on 12th June. I can see the image in the configured upload channel, but they do not display in the target channel. We are running 0.48.13.

I've tried re-creating the integration app, no change.

What about the channel where slack sends the images?

ok so there's a common pattern: all users that reported this are in different versions and now everyone does not get the images attached. Slack here needs to respond as they changed the api without giving notice