MTN call center

I was due for an upgrade at MTN. When I gave them a call me and the service provider agreed on a certain contract. He told me it would be activated within the next few days. 1 week later I gave them a call they said that my contract is still being processed. After 2 weeks I called them back they said my application got cancelled because they didn’t verify it. Now I app**** for another contract because they didn’t have the same option I wanted. This contract went through. At the end of the month they charged me R1000 more for the previous month which I’m assuming because I didnt change my contract. It’s not my fault that MTN didn’t processes my new contract or at least inform me whatever is going on. MTN records all the calls they can go back into the history and see that it’s not my fault. I’ve called MTN they said they will look into it and get back to me within 72hours. I got a reference number for it. I did get an sms saying that my inquiry has been completed. No further info provided. Today I phoned MTN again they put me through to the retentions department. I’ve been on hold me a long time and no answer