Double Charged on Contract since July 2015

I have two contracts with Telkom Mobile. The contract reported on was opened in July 2015. I was issued with a device as well as a sim card. The sim card was ported to my previous number, and the issued number was supposed to be cancelled. I was contacted twice by Telkom Mobile with regards to the cancellation of new number. I had then noticed that I was being double charged on the new contract, and I had opened up a case with billing (Case no: ***4). I have spoken to numerous people, doing follow ups from my side, and nothing was sorted out. Eventually I demanded to speak to a manager, Brenda, who noted the case and was to confirm the resolving of the case in 12 hours. This call was made on 1 October 2015. I have made many calls since to speak to Brenda, I am always told she is busy after I provide my name. Call centre agents assured me that they have sent emails to her to contact me, but I have heard nothing since. This is the second time that I am posting issues of Telkom Mobile on HelloPeter. It seems that everytime I interact with Telkom I am showed no good customer service and no resolving of issues. I will never recommend Telkom Mobile to anyone based on Customer Service