Unknown column 'source.xxx' in 'field list'

Hello,

I have been experimenting with custom questions (specifically pivot tables) and I keep getting the following error when I try to create a "custom column" that multiplies two values in my "summarize" field list: "Unknown column 'source.xxx' in 'field list'". Most of the Metabase forums I looked at say that if I am running a version >= 0.39.0 that I should not be receiving the error.

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    "vendor": "Google Inc."
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  "system-info": {
    "file.encoding": "UTF-8",
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    "java.runtime.version": "1.8.0_265-b01",
    "java.vendor": "AdoptOpenJDK",
    "java.vendor.url": "http://java.oracle.com/",
    "java.version": "1.8.0_265",
    "java.vm.name": "OpenJDK 64-Bit Server VM",
    "java.vm.version": "25.265-b01",
    "os.name": "Linux",
    "os.version": "4.15.0-143-generic",
    "user.language": "en",
    "user.timezone": "America/Chicago"
  },
  "metabase-info": {
    "databases": [
      "mysql",
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    "hosting-env": "unknown",
    "application-database": "mysql",
    "application-database-details": {
      "database": {
        "name": "MySQL",
        "version": "8.0.23"
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      "jdbc-driver": {
        "name": "MariaDB Connector/J",
        "version": "2.6.2"
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    "run-mode": "prod",
    "version": {
      "tag": "v0.39.1",
      "date": "2021-04-27",
      "branch": "release-x.39.x",
      "hash": "6beba48"
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Please advise at chance. Thank you.

Hi @dereksteiert
Post the full stacktrace from Admin > Troubleshooting > Logs.