TestFlight: Cannot add internal group to a build

[VIadislavJevremovic]

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Which mobile framework are you using?

iOS (Swift, Objective-C)

Steps to reproduce

I used the following snippet for TestFlight distribution in codemagic.yaml (this is the only troublesome part, the rest works quite well):

app_store_connect:
  auth: integration
  submit_to_testflight: true
  expire_build_submitted_for_review: true
  beta_groups:
    - Team-1

Expected results

Build is assigned to a specific internal beta group on TestFlight.

Actual results

The following error is encountered at the end of post-processing step (build is actually assigned to all the internal groups on TestFlight):

Adding build '902b5448-2874-4bef-9667-3cd385e5ec22' to the following beta groups: Team-1.
Failure: Failed to add a build '902b5448-2874-4bef-9667-3cd385e5ec22' to 'Team-1' beta group. Builds cannot be assigned to this internal group. - Cannot add internal group to a build.

(Beta group assignment does work well for Firebase App Distribution)

Build id (optional)

66260fb568d504f180d0c1f0

[VIadislavJevremovic]

Solved: internal groups need to have Manual distribution type in TestFlight (not Automatic as it is by default).

[galvesribeiro]

Here is how it was fixed: fastlane/fastlane#22051 (comment)