Cancellation of contracts

I cancelled all 4 contracts in May 2014, but i still get billed. On inquiring the big amount that was debited in November, I was informed that my account doesn't reflect as settled! I got a ref. no:41******27 and was told that it would be sorted out right away! But then I got a shock of my life when they tried to debit just over R5000.00. I contacted the call center and was given another ref. no:50******14 and was told again that it was marked as URGENT! and it will be sorted out with in 2 working days and that the money would be refunded! Today i received another call asking me when would I settle my account of R5000.00??? i phoned the call center yet again and got the same response, this account does not show as settled but all the numbers were transferred to pre-paid and we will mark this as urgent and sort this out for you as soon as possible! I paid this account up 9 months ago, why can no one find the recorded conversation? Why is my account still being debited? What do I have to do to get this nightmare to end? How do I get my money back that was taken without my consent?