The strange thing is that my cell phone always has internet via WiFi. But then I have problems loading certain pages. The LEDs on the router always flash differently as I have set them up!
My girlfriend usually doesn't have any internet on her cell phone and a TV via WiFi as well.
Unfortunately I can only access the OS via the app via WiFi. Whenever the router causes these problems, I can no longer figure it out, even though my cell phone is still connected to the router.