Poor DStv customer service

A DSTV agent has made a R99 sale on my account, I have called many times to cancel the subscription and every month I am being billed for services plus R99.00 Every agent I speak to says they are escalating the matter but they dont. I spoke to 5 or 6 different agents between Thurs and Fri last week and all of them did nothing. Now all i wanted was for the add on to be cancelled, but with all this disgusting low levels of customer service, I want my money back dated to the inception of this add on.