BLACKLISTED A YEAR AFTER CANCELLATION

I had cancelled my mtn contract in Feb of 2014.I had settled the last installment and it was told to me by the cancellations dept that the account was closed. Now I am told by Experian that MTN has Black Listed me. After holding on for almost an hour and being transferred from department to department im told by a legal consultant I have to pay R218.11 in order to remove my name . MTN had not contacted me once to tell me im in arrears .they listed me in November 2014. There was no correspondence to me at all from Feb to November. my account was settled and cancelled in feb 2014 . I had given the consultant the details of the cancellations consultant I had spoken to. he did not want to listen to me and just insisted that I settle the outstanding amount . Since Monday I have sent numerous emails to the consultant and the customer service dept.i have not received a reply as yet .I have even paid the outstanding amount and sent through the proof of payment just so that my name is removed. STILL NO REPLY. I want to know how was I black listed without any correspondence from MTN to date.