Here is a sceenshot from a customer that is not able to sign up.
Unfortunately it is in German.
This appears, when a customer wants to sign up with a google account
TRANSLATION:
Access Blocked: Google’s verification of auth0.com has not been completed.
The app is currently being tested and only the testers approved by the developer have access…[…]
But I don’t give any explicit permission. other users can log in without any problems. So far only 2 users have reported this problem to me.