Cancelled contract.

I had a cellphone contract with telkom two years ago. When the contract expired i had filed for contract cancellation online as it was impossible to get hold of the contract department over the phone. It seems like all went well because they stopped debuting for the cellphone contract. But there is an amount of money which is less than a 100 that they are debuting me for, i tried to query for it and i had no answers on what is it for. Last night they have debuted an amount of R800 and some change from my account this is after a year of ending a contract with them. May they please kindly explain this and i want my money back.

I wrote a review about them sometime late last year and thy have never contacted me.