Telkom 3G service does not work

I have been emailing and contacting Telkom for as long as I can remember. I have complained on numerous occasions that my internet does not work, or it is extremely slow, it does not even want to open email or Facebook. It basically does not work. <br> I am paying for a service which causes a lot of frustration when trying to use it.<br> This has been ongoing for quite a while and the problem does not seem to get resolved. <br> I want to know if I can cancel my contract as I am not getting any joy from it in any event.