CANCELLATION ISSUE

I have had issues with Virgin active basically from beginning of the year and due to that i have had to cancel my contract. I phoned in to make payment arrangements in Jan. They said they will let me pay R430 for 3 months. Feb was ok. March they deducted R860, i phoned it was fixed. They said they will correct the system. April came they deducted R860 again. I then mailed and cancelled my contract. May came they deducted R860 again. I have told them telephonically and by mail that i have cancelled my contract. Still to today i get emails regarding ny account that has not been paid. I have bot been to virgin for over 2months now. PLZ CAN YOU CANCEL MY CONTRACT. i am so disappointed in the service and never wanted to cAncel. But they left me no choice