Telkom just ignores refund, hoping it will go away??

Dearest Telkom, would you please let me know how to go about getting my refund from you? I cancelled my account, thank goodness for that, but it was left with a positive balance. Since then, another automated payment was made, pushing the credit to R2070.68. I have logged a call, and apparently the call was "actioned", but there are no updates, and more importantly, NO MONEY paid back to me. This call was logged on the 4th of April, btw. I know from experience that you are VERY quick to deduct double payments when your payments are missed by a few days, and that you are also very quick to send threatening emails from your "collections department" which loves adding admin fee's and such. So how do I go about to get my money which you now owe me? My next step would be to get legal advice, which I would happily do, even if it costs me more than the R2000 you owe me, purely out of principle. I am looking forward to your response, and better, to getting my money back.