Being made to pay for DSTV Finance department's mistakes

This is actually a follow-up to a review I posted a couple of weeks ago that was unfortunately removed from this side. Multichoice terminated my services at the beginning of August although I have paid for the services and have been paying every month since the beginning of the year! What happened is that in February due to incompetencies of their finance department, they dublicated the payment that I made end of January. Some time in or around March, I downgraded my services and subsequently I started paying the subscription amount for new downgraded package. By the end of July, they realised the mistake they made in February and reversed the duplicate payment. After this they decided that I owe them as they say they have been providing me with the VAS during this time that I did not pay for as I was paying the premium for the downgraded services. All this whilst they should have suspended my services if the services were not paid for, but because they have provided my account with a cushion by the duplicate amount they put on my account, now I have to pay for their mistake. Imagine now I owe a vendor that is not a registered credit provider. The consultant I last spoke to, said she was gonna get her boss to give me a call to resolve this. No call whatsoever, and it is more than two weeks ago!!!