I have same problem like yous, but I'm not sure if the reason is the same.
I change my app name on app store connect, the new version upload on testflight successfully but we cannot install the app.
I use Ionic to build iOS. I changed all configuration about app name and deleted the generated ios directory, then rebuilt and uploaded. It was resolved.
Topic:
App Store Distribution & Marketing
SubTopic:
App Store Connect
Tags: