Loan settled, but money still being taken

This is turning out to be the worst banking experience of my life! I received a settlement quote on my personal loan ob 23 October 2018, which I PAID IN FULL on 23 October 2018. R885 went off my account around 27 October 2018. I queried that debit order and was refunded. When I contacted FNB to ensure that the loan account was being closed, I was informed that it wasn't even in the process of closure and that I still owed R885.42 to settle the loan. This after I was told that it was an error on FNB's side and that I would probably not be liable. Then I was told that I owed it because why bother paying a settlement amount that I had in writing. Nevertheless, I paid that amount on 27 November 2018 to just close this damn account. I thereafter contacted the loan department and it was confirmed that the money had been received and confirmed 4 times (check your recorded phone call) that there is no longer money outstanding on the loan so the account will be closed. On 28 November 2018, I received an imterim paid up letter. Here's the part that gets my blood boiling even more - TODAY, 29 November 2018, I see that FNB took R885.42 off my account for this loan on 28 November 2018. IT WAS SETTLED SO WHY THE HELL IS THIS ACCOUNT NOT CLOSED AND WHY THE HELL ARE YOU STILL TAKING MY MONEY?!?! I WANT THIS LOAN ACCOUNT CLOSED TODAY, NOT TOMORROW, NOT IN A WEEK, TODAY!!!!!!