Refusal to refund money

I am still trying to get my refund of an overpayment on my dstv account. It has been refused as I can't print proof of payment for 6 months off standard bank - it doesn't allow you to. All id documents, copy of bank statement, copy of account and 3 months payments have been sent to multichoice and they refuse to refund my money. I have stopped the dstv and they are just happy to keep my money like ******* in the night. Are they really serious.