MTN listed me on Experian system for no reason

I infrom MTN on the 17/02/2015 to stop my contract witch end at the end of April 2015. On the 22/05 I again send then follow-up mail because they took the instalment form my account and I infrom them that I give my bank the permission to send the payment back. On the 01/07 I again send them email because they again took a dubble instalment from my account. I again infrom them I instruct my bank to sent the payment back. On the 21/07 I agian send them a mail that I again going to sent the payment back. On the 21/07 I received email from MTN and they promise me that they will resolved the matter within 3 business days. On the 24/08 I received confirmation that the service has be deactivated, however there was usage on the account. On the 25/08 I ask them to send me the oustanding amount and I will pay it. No feedback on the amount outstanding. On the 10/09 they refer my account to the legal department and said account has been handed over. On the 17/09 I received mail from MTN to infrom me that my account has been refer to the ***** dept. i am busy purschase a new car and my bank infrom me that I am listed. I want my name to be removed ASAP becasuse I am not going to loss the deal.