(hosted instance: forum.plentymarkets.com)
One of our users (Pixelfreaks-dev-27139) can’t change his email. He gets the error
change_email.error, saying a user with this email already exists. However, this is not the case.
He already hat issues with changing the email address in the first place, he got the same error there. As I tried the same thing by taking over his account with my admin account, it worked. Spooky, somehow.