TestFlight access stuck on old device

Hey all — hoping someone here has dealt with this before.

I’m testing an iOS app via TestFlight, and when I originally got access, I didn’t have an iPhone. So I signed in with my Apple ID on my girlfriend’s iPhone and used TestFlight there. Everything worked fine.

Now I finally have my own iPhone (iPhone 16), downloaded TestFlight, signed in with the same Apple ID, and had the developer resend the invite. But when I tap "Open in TestFlight" from the invite email, I get this error:

“Couldn’t load app because your Apple account has already been associated to this app.”

The dev tried removing me as a tester and re-adding me, I’ve deleted TestFlight from both phones, rebooted, reinstalled, waited in between — still no luck. Even tried opening the invite link in Safari instead of Mail.

Is there any way to get Apple to fully reset the association with the old device so I can use TestFlight on my new iPhone? Or do I really need to make a new Apple ID just to get around this?

Any help would be huge — thanks!

TestFlight access stuck on old device
 
 
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