Incorrect Debit Order

I had a Cell C data contract and have cancelled it after going into the cell c store in Mall @ Reds. I was told to call the call centre to cancel as the branch cannot help me. My debit order was for R119 and a limit of R50 was also placed on the account. They now put through a debit order of R 478 and after calling the contact centre, i am told it is for November subscription even thou the contract expired in October and i was charged R 399 and was not used in November. The Debit order is being processed every week on my account and due to the fact that i have reversed it, my account is now handed over to legal without even informing me or trying to resolve the matter. This is my last option in trying to get some proper feedback or assistance.