I recently got a new telekom sim card but I'm really struggling with it. I live in the city (Dusseldorf) and I need the internet connection for work (which is why I chose to have unlimited data) but very seldom does it work for more than 20 minutes in a row and as soon as I walk into a building I no longer have signal. I usually have 1 or 2 bars. I tried to contact customer service but I don't speak German yet and those who could speak English couldn't help me. I really don't know what to do.