Telkom wrongly debiting my account

Telkom keeps deducting money off my account, I have canceled my contract with them almost a year ago, and still they are deducting random amounts of money off, which I keep on declining. Seriously Telkom. I had a wifi router specifically asked for a Capped contract, then without confirming or notifying me they changed the capped to an open account, i went into the branch to see what is going on, they apologized and said it was a mistake and not sure how it happened, they kept the account running opened, I canceled the contract as this was not my agreement with them. I served my 30 days notice period, and they stopped debit payment order for about 5 months, then suddenly started again deducting money. The last 4 days they did 4 different debit orders with different amounts. Looks to me like *****!!