Updating of paid up loans

I took out two immediately loans with FNB in 2019 and both were paid up in the same year but both still reflects as unpaid and active on my credit score. I have requested FNB to update this endlessly and they fail. They gave me paid up letters that I have been sending around and still the two accounts reflects as active and unpaid. Why is FNB failing to update accordingly over 2 years already