Bad customer service

I recently signed up with I-Spot,a company offering a Wi-Fi internet service . The technicians came over and installed the necessary equipment (which was at a cost)and ever since 11 August I have been having endless internet issues (dealing with online gaming)which I did report and however I'm still awaiting a way foward and nothing has been done and no effort has been made to ensure I'm getting the service I'm paying for and deserve as a customer. In my complaints to them I did state that then I had a previous Telkom ADSL and I didn't have these issues even though that line was much slower. Another thing I did mention was that signing up with I-Spot was solely for online gaming and at the moment I am unable to even play a single game online and yet I have been already sent invoices which include my installation fee and monthly premium which is due at the end of this month. I have already complained on numerous of occasions and nothing seems to get done.