I no longer live in Germany and I don't have a valid/active German Mobile No.
I can't log in because it requests for authentication everytime I log in and that can be done only on Mobile no through text or call. But I don't have an active German Mobile No. I have tried calling customer care but have not had any success.
why was your attempt to contact customert support unsuccesful? its the only way to resolve this. on workdays you can ask for an english speaking supporter and from then on its a pretty easy task to do.
