[Self Hosted] Got verification email, but verification self fails


i have a working Bitwardenservice hosted on my own Server.

Everything works, execpt the Verification. I get the Verificationemail, copy the Link, add my custom https Port to my domain and submit it.

After few Secounds a Popup in the right upper Corner shows up with this text:

“Ihre E-Mail kann nicht verifiziert werden. Versuchen Sie eine neue Bestätigungs-E-Mail zu senden.”

In english: Your email cant be verified, please try a new verificationemail

In the logs is nothing.

2 Days ago, everything worked. Even the verification self.

Since then, nothing changed.

Have nobody a idea?