Mtn billing me for an item i do not have

My experience with MTN this past few months have been unwanted and unnecessary. I ordered an item tellephonicaly and the item i wanted was not the item i received because the lady who helped me took it upon herself to decide for me when she saw that my credit does not apply for the item that i want to send me the item that i dont need nor want same day i received my package i returned it to mtn store witch they gave me a reverence number phoning the item and reverence number in to head office telling me that the account will be cancelled and removed from my name since then its been problem after problem they keep billing me for an item i do not have and i have proof of the return spoken to many consultants agents and managers that are completely useless.