1&1 DSL services (Berlin)

Dear expats, i would need your feedback/experiences. I've signed a contract with 1&1 for home internet. In the last week, I've experienced a few 4-6h blackouts (connected to my network but no access to internet). All hardware and plugs are fine. After reporting the problem, i got a response from the customer service, written in perfect English, that I need to write the report in German-which i did. Than a response my German was not good enough and a native speaker should write it?! Than again, after a colleague wrote them -no reply. What are my options here? Has anyone experienced such a thing in Germany? Thank you in advance. Best, Tamara