MTN clear my name

In 2019 I had a contract phone with MTN unfortunately I lost my job and was unable to pay. In 2020 I found employment and called MTN to find out how I can settle the account and referred me to Veri cred. I made payments and completed it but now MTN is refusing to clear my dept on their side which is making it hard for me to buy a house. MTN I paid your money why are you not clearing my name I've sent you the statements from Veri Cred yet everyday when I call you telling me your system is offline when does your system ever work