Benutzeraktivitäten

A vodafone door to door salesman came and he offered me gigakombi connection. I didn't know German and he said that he can translate everything for me so that I can understand the terms.He said that my number wil not change and I'll only have to pay ...
I paid my vodafone cabel bils via bank transfer but the portal is still showing outstanding balance. What should be done in this case?I am an english speaker so I can't reach the customer service, the computer speaks german