Entering Test-Information in TestFlight fails

I'm trying to enter the requested information for a new build of an app, but the system doesn't recognize a valid phone number :-(

Every help is appreciated Peter

I've solved the problem with the phone number. One has to enter a full international number like +49992814094850 The error message that the phone number is only allowed to contain numbers is wrong and doesn't help. You have to do the exact opposite, namely insert a + which is in no way a digit.

Entering Test-Information in TestFlight fails
 
 
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