useless

I cancelled my tablet contract in november and now they deducted money off my account for it after it should been cancelled. I had it reversed and logged a call about their mistake. But once again the next month they did it again. I reversed it again now After going in store last saturday to make payment and to sort the issue out again they put a trace locator on my credit and this is after i found out someone didnt cancel my contract at the head office.