pikimaus, it looks, that I have to write in English. I don't speak German. In order to completly delete your account, you have to contact the Abuse Team. (Select "Other" as Abuse Type). You may have to send some proofs to ensure, that the account is yours. Only the Abuse Team can take measures in this situation.
Bitte, sagen Sie uns, warum haben Sie Ihr Konto löschen?
I wanted to say, that please, tell us, why did you deleted your account? This information will help us to improve the quality of our services.