Billing nightmare

I have had the worst experience with MTN for over 6 months now. I was getting double debited by MTN and I kept trying to resolve this matter, after several calls to their call centre and several store visits to their Queenstown branch, all I could get was an admission that there is an error. Apparently they had changed systems hence the incorrect debits. But no one was resolving this issue instead it kept escalating to a point where one month I was debited four times the mount I signed up for. I then resorted to reversing these debits and informed them to give me the correct invoice to settle, still I got no assistance on the matter and the incorrect amount kept being debited. I asked for a quote to cancel my contract and was given the runaround so I continued to reverse the payments. MTN has now suspended my service and I cannot make outgoing calls, I have been requesting the correct invoice and days later I still don't have it. To make matters worse one of the numbers they suspended is not even on contract. As a customer I feel bul**** by MTN.