MTN DOESNT CARE ABOUT THEIR CLIENTS!!!!!!

I'm harassed by MTN!!!!!! i had a contract which is paid up and closed. But they didn't update my payments credit bureaus, it appears as in arrears. The account was closed 4 or 3 years ago but it still appears as owing them. When I call the call center they can not help me i must go to the branch. when I get to a branch I must call a call center. I had to pay a legal team 4100 and something rands, but the account number doesn't exist!!! They are quick to say they give the best service but when it comes to delivering, they FAIL!!!!!!!!!!. Disaster now my credit score is affected because they say my mtn account is in arrears and NO ONE can assist me!!!!!!! No one tried to call or contact me for this matter!!!! So disappointed and feels like they don't care!!!!