Heres an english translation of his quote, for those you of who don't speak german.
Very honored STRATO customers, very honored STRATO customer
Regrettably payment difficulties appeared for your customer account. For this reason we see forced ourselves unfortunately to restrict some services.
Possibly we have not your current data and were not able to carry out therefore the load writing. Please you review under contract care - change of the tribe data your bank connection, your address and your E-MAIL ADDRESS.
In the area your calculation Online you receive detailed information to the yet open sums. They have there moreover the possibility to cause the load writing again.
As soon as the yet due sum went in here, is available you the STRATO services obviously again in the full circumference.
We regret the unpleasantness and be thankful for your support.
With kind regards
Your STRATO team