Dstv wrongfully deducted my money from my bank account.

I have just experienced day light ******* from dstv multichoice along with the most disappointing customer service ever, DStv decided to debit my account while I have over R1000 credit on my dstv account. To add salt to injury they have set up their customer service calls such that you don't have an option to choose for an operator regarding account issues unless you opening a new account so you spend a good 10 minutes hoping to get an option that will allow you to speak to an operator but nothing, I eventually got hold of operator who were mostly clueless the made me hold for over 30 minutes and refused to call back as if being ****** R850 from your bank account was not bad enough now you have to spend a fortune just to get the operator to assist with your problem. I eventually get through to an operator that was keen to help who then informed me that Dstv was charging me twice everymonth for the past 5 months. When I opened my dstv I made it clear that they must only activate 1 of my account therefore I want dstv to pay me back my money all of it. I refuse to pay for their mistake.