Using the iOS profile, my CalDac and CardDav passwords are not accepted. In contrast, IMAP works fine and I have access to my emails. I also tried AppPasswords and deactivated 2FA for the admin and mail accounts, however, the problem is still there.
Additionally, I am also not able to connect via Active Sync. I assume, it is the same password issue.
Using the Microsoft Connectivity Test, I receive the following results:
