Open account after settlement

I happen to have an account with MTN of which I called to cancel and I was told the balance that needed to be settled in order for them to close the account. I made that payment and the assistant was able to verify and close the account on her end.

Later on in the stage I realised that this MTN account still shows as open under my credit score report. I contacted MTN and they assured me that the account was indeed closed. I just gave it some time to clear up but nothing.

I decided to open a new account with them as I had wanted to purchase a Laptop, unfortunately I couldn't open that accounts at MTN because the account still showed as open at their end, I contacted retention department again and I was told that I had an outstanding balance of less than R50 that needed to be settled first. I was so frustrated because I was not told about that amount before and why would they close the account if the money was short paid?.

I paid it in December via EFT and till January they claimed that the amount was not yet reflecting on their system. Again this account is still opened on my credit score. Since last year I have been following up on this account with no conclusion. I still can't open an account nor clear that on my credit score report. Today 16/02/2023 I called the retention department and they claim that the account has been closed.

Right now I'm so frustrated and hopeless, I want this account removed.