Netstar stil debiting my account after I cancelled

I have been trying to cancel my contract with Netstar for a vehicle that I sold more than three years ago. After sending you a cancellation letter numerous times. My account is still being debited, even after I put a stop order on the debit order. Everyone out there should be warned that trying to cancel a contract with Netstar is basically impossible and trying to make them stop taking money from you is even worse. Never again will I even consider Netstar