Testflight error "Your request couldn't be completed"

Im updating an old webview based app, i remade the app and its working on xcode. I would like to test it on my iphone, via testflight but when I try to install i get the error "Your request couldn't be completed". I've searched online but couldn't find a good result.

I tried to change the Code Signing Identity, but that doesn't work, because I have automatically manage signing turned on.

Did someone encounter this problem and how did you fix it?

I'm not sure if this is a coincidence, but I also have an iOS app that uses a webview. I encounter the same issue in TestFlight when trying to install the app. Could this be related to using a webview?

Testflight error "Your request couldn't be completed"
 
 
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