Hi,



Phone or livechat are possible ways (not all speake english), but in my opinion it is the best way you write a letter with youre questions, includs youre adress, custem-number, copys of documents and on top the word "Rechnungswiderspruch", and sent it to o2 by post or fax



Telefonica GmbH



Überseering 33



22297 Hamburg



or fax 01805-880088



Remeber that you can sent fax from youre PC with a programm like PDF24.



Greetz

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