MTN ****** me and ruined my name

I took out a contract with MTN in March, the sim card hasn't worked since from then, I called send emails but till this day they haven't helped me worse part they now black listed me and handed me to legal. I called to get the amount I owe because I ddnt want the whole thing to affect my score, I paid the full amount called the MTN they told me they can I have paid but legal still refuses to remove may name this Hass been happening for 8 months it's really frustrating because I paid for a service I ddnt get and still they won't remove my name from legal