Update my credit records

Hello Norman bissett & Associates group is not treating me well i settled my African Bank account in 2018 but I still complain even today, my problem now is I do get the payed up letter but in Africa Bank I was told that there is nothing they can do about that letter but my account in no longer in their hands so I'm begging please up data my credit score in the credit berrue so that I can get a chance to get a loan please