HORRIBLE SERVICE!!!!!!!!!!!!!!!!!!BAD

HORRIBLE SERVICE !!!!!!!!!!!! I am at the edge of exploding out of anger and frustration, I had an amount that was outstanding back in 2021, that I paid in full November 2021 and settled the account, letters were sent etc but I was never removed as owing, since then I have been struggling to get my name removed from credit provider it is now reflecting on my credit and is affecting my credit score!! MTN has given my account to legal but I do not owe them any money, with ever call and email done to MTN I have been told its still open we must wait, now its been 13 months and till date no assistance from MTN what so ever. PLEASE HELP ME!!!!