Very bad experience with FNB

Very bad experience with FNB. I am trying to close a revolving loan account that is fully paid off, but I get error Error code: 17124. What the hell does this mean? To make matters worst is that when I called them I kept on being sent to different departments as no one knew what the error code meant.

I tried more than 5 times to close this account with no luck. Maybe this is your way of making sure that people say in debt by failing your system on account closure.