Failure by FNB to update ITC with payments made on the loan

I took a loan with FNB sometime ago, I did not make payments on the loan and it was handed over to debt collectors. I made an arrangement with the collectors and paid every month as was advised to make debit orders.

When I went to my credit profile to my surprise I see that for year 2020 I have multiple missed payments though my statements show that payments were made to the collectors. When I contact the collectors I'm told FNB have the responsibility to update my credit profile. Because of the multiple missed payments that are incorrectly loaded on my profile, I cant get any credit elsewhere because the history shows that I did not make payments according to the arrangement I made.

As I was so frustrated I opted to close the account by requesting a settlement quote I paid the amount but still this loan is still sitting on my credit profile. Now I don't know what I should do to clear my name.