MTN debiting accounts that have been cancelled

The most pathetic service provider in SA! Payment was made for cancellation of a contract on the 3rd of November yet my account was still debited on the 1st of December. I have sent 24 emails to which no response has been received and no progress has been made. If I go in store I am told that I need to call the call center. After being on hold with the call center for no less than 45 minutes at a time, I was told that this is my fault as the incorrect reference was used. This reference was on the mail received from MTN with the cancellation details.