Getting debited even after I cancelled my contract!!!!!

I have sent these people emails and called several times to cancel my tracker with them and the service has been nothing but pathetically POOR! First of all, they only reply to emails 2-3 months later and they only respond when they want money! I sent them all the necessary documents to cancel but they keep debiting my damn account.!!!!!!!!!!!And when I call the call centre I am given attitude and told to pay the money or else they will note it on the system that I am refusing to pay. I AM REFUSING TO PAY BECAUSE I CANCELLED MY ACCOUNT 4 MONTHS AGO! This company is misleading and full of empty promises. Whatever you do, do not get your tracker from them. They are useless! Including their rude call centre agents!