I'm having this same issue. Mine is trying to run a Unity ARFoundation project, Xcode 12.4, to a dev iPhone (auto signed and connected via USB) on 15.1
The AR is embedded in a Flutter project, the rest of the app runs fine until launching AR.
Also works fine on Android
WallyHale
Users receive reputation points by contributing quality content to the forums.
Posts include post and replies published on the forums.
Post authors can mark replies as Accepted to indicate successful solutions.
Apple Developer Forums admins can mark replies as Apple Recommended to indicate an approved solution