Hello. I live in Berlin, today 2 employees apparently from Telekom knocked on my door, asking if I wanted to register my contract for optic fiber just. I said that I did not receive announcement of their visit and I was suspicious about them, but they insisted in talking and after some conversation, one of the two guys asked for my birth date and contract number, but when I realised they were filling in data on an electronic form on their tablet, I did not give them any more details and told them to leave, I was very worried. They told me I would get a letter about registration in 2 weeks. I am afraid I have been scammed or singed up for some additional contract: what should I do to protect myself? Should I cancel my Telekom contract immediately to avoid problems? Any advice is appreciated.