Telkom Wi-Fi Services

My Mom's home Wi-Fi router has been giving us problems and we have called Telkom and told them that the router isn't working and they couldn't explain why it isn't working and it's going for the 3rd of 4th week not working, we have sent them an E-mail but still noting from them trying to fix the Wi-Fi I'm so fed up and unhappy with Telkom's services and they are offering a bad service by that time we are paying for they services and they have been double charging my Mom for her portable router that I have been using and they claim that we have been toping it up but it has never been toped up not even once.

To a point that I told Mom that we should leave Telkom cause they services are not good and she isn't happy with it at all.

I would like a good explanation for they bad services and the double charging that they have been doing.