Pathetic vodacom service, again! Over you!

In March 2015 I cancelled a contract that had expired with Vodacom. Vodacom subsequently billed me for BIS for 2 months after that. After receiving the first invoice i contacted them and after speaking to less than 3 people I was assured that this was an error and that I would be sent another invoice indicating that I owed nothing on that account. Subsequent to this, at the end of June I was debited R118. I then received a letter stating that my account had been settled and that this had been reported to the credit bureau. I called Vodacom for the umpteenth time to complain about this unauthorised debit and the fact that they had tarnished my impeccable credit rating over a sum that I did not owe them. I spoke to 3 people who could not resolve my issue as the number is now prepaid. I received this call and spent 30 minutes on the phone trying to explain to the person my problem. He promised to call me back and he never did. All I want is Vodacom to inform the credit bureau that they made a mistake and for them to give me my money back. I have spent over 4 hours of my life trying to resolve this and I am tired of their poor poor service. I am considering cancelling my new contract.