Unauthorized debit/cancellation of contract

My contract ended with Telkom , called the call centre to cancel no cancellation done , The retention department called for an upgrade and I advised that I would like to cancel they sent " a query" through for cancellation still no cancellation done . I have tried on numerous attempts to cancel my contract still no joy , I ended up disputing the payment and stopping the debit order but Telkom resubmitted the amount on the 25th and sent me an arrears message . SO TELKOM ARE YOU FORCING PEOPLE TO KEEP CONTRACTS WITH YOU WITHOUT A NEW DEVICE OR AIRTIME LOADED AS WELL . SO YOU ARE DEDUCTING MY MONEY FOR WHAT ???????????