Bunch of *******!! Account settled but they keep charging for no reason and do not update credit bureaus

I took a loan with these people. Their app is nearly impossible to get to my new phone so to save me my hassles i settled the account with them. I went directly on their app on my old phone and chose settle account, the app had the settlement amount - note that we do not put in a value it is automatic. Then i had to choose a date and i did and the money was deducted off my account.

I called in to ask why it was not updated on the credit bureaus and i was told it will be the foloowing monday and that it took 21 days. Then for a paid up letter and was told that it was sent to me an that I had received it. I saw that it was still not updated on experian so i then disputed the account because it had been paid up. They asked for a paid up letter. Today i called african bank for the paid up letter again. This time they said that i have an outstanding balance and the account is active. I have not used that account i settled it directly off their app. When i called the first time the cinsultant vinfirmed it was settled and that she sent me a paid up letter, she also confirmed that it was going to be updated on the credit bureaus. I had no outstanding balance. I want my paid up letter. Why is it suddenly still active? They debitted my account of the full amount so it cannot even be said that i paid the wrong amount