Trying to cancel account - no response

I have been trying to cancel my Telkom mobile account for over a month and have had no correspondence at all. I have been receiving smses from Telkom since August last year (when my 24month contract was done) to say an agent will call soon to discuss new products etc so I thought I would wait for that call to try and cancel. The call never came so I emailed the cancellation form to the cancellation department on the 4th of Jan, no response so I emailed it again 2 weeks later. Still nothing so I went to a branch last week Friday and was told they cant cancel but can only log a case which the lady did. I then called this morning to follow up and was told an agent hasn't been assigned to my case and need to wait a few more days to follow up again as the call centre cant assist in any other way. Every month my account gets debited and I cant use the service. Network is so poor and slow its pointless even trying to use the internet. This seems like a money making scheme by the company because the longer they take the more money they can ***** from us. If they say their cancellation dept is so busy that it takes so long to get back to us, one has to think about their services