Unauthorized debit order after confirmation of cancellation received.

I had a contract with telkom were I was paying R99. 00, I cancelled the contract 5 months later I am being handed over to the lawyers because I owe R1094 on the account even though I havent been using the data or airtime, I paid the lawyers the amount and they sent me a confirmation confirming that the account is settled and my account had been cancelled. on the 15th of March they tried to debit be R216 without prior notification, my bank ended up charging me an unpaid fee of R130... I called Telkom's cancellation department, they referred me to billings billing then said I still owe them and I need to pay before I can cancel the contract.