I've encountered a problem in Testflight where we had previously signed up an external tester using a non-Apple-ID related email address, then brought them into our internal team and invited them to the internal list via their actual Apple ID. After they attempted to install the app as an internal tester, they recevied an error message saying they had already been invited to test flight when they tried to download a newer version of the app. At this point, the user cannot install the app either as an external or internal tester.
Attempts to delete the test flight profile, delete the tester from the interal and external lists, delete the app, and re-invite them only leads to the same error happening. The user is effectively locked out of test flight.
Has anyone encountered this issue and found a workaround?
Thanks!