Dear Community,

Unfortunately I can't speak German, and I find it really hard to get answers, so I hope somebody can help me here.
I am using Tmobile more than a year and I didn't have any problem about my internet or modem. But two days ago, my modem's green wifi light started blinking. I have Speedport pro plus(black tiny and tall one). 

Later I tried to restart, reset, return factory settings, I tried restarting, and unplugging - waiting - replugging again, etc but it doesn't work. I can use internet with cable but wifi function is not working. Actually I can't see my wifi name in the wifi list of any devices. 

I then tried to call the service number, but I don't understand it. They said your internet looks working. Yes my internet working but my wifi is not working so I can not use my internet. I'm working from home and my modem is in kitchen. So I can't use it via cable. 

I'm looking forward to any suggestions or help,

Thanks in advance.