"There was an error processing your request" when adding build to External Testing group

I'm unable to add a build to an External Testing group in TestFlight. When I click "Add Build" on the group, select the build, fill in the "What to Test" field, and click Submit for Review, I get:

"There was an error processing your request. Please try again later."

App: Glimpse Meet people (com.salarumer.glimpse) Build: 1.0.0 (14), uploaded Jul 4 2026 Binary State: Validated

The build exists in the iOS builds list and is fully validated — the error only occurs on the final "What to Test" submission step when adding it to an external group.

The issue is not isolated to this app — I'm seeing the exact same error on a separate app that is already published to the App Store. This rules out a build or metadata issue on my end.

I've tried:

  • Approaching from both the group page (Add Build) and the build detail page
  • Different browsers (Chrome, Safari, incognito)
  • Waiting several days (issue started ~Jul 4 2026)
  • Contacted Apple Developer Support (Case ID: 102933411126, no reply in 7 days)

I am getting the same thing. My app is approved for internal testers but I when I open Testflight on my tablet to install the build it says the build doesn't exist. I have a green sheck on my build and my EAS build succeeds.

"There was an error processing your request" when adding build to External Testing group
 
 
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