Refunds ******

I've settled 2 outstanding loan amounts I have with FNB. The accounts both reflected a balance of R0.00. Come month end they took the amounts which is close to R6000.00. I lodged a query and received a response from FNB. The money will be paid back. After a couple of days the money was not yet paid to my account. I lodged a query again just to be informed that the small amount was paid back but the R5500.00 will not be paid back as they took it for interest and a settle amount. This is the first I've ever heard of this before. I have settled a couple of accounts before and it cost me less than what the current outstanding amount was. How come I must pay interest on a account with a balance of R0.00 and pay to settle the account and such a high amount too. This is ****************. I've been with FNB for over 10 years and for the first time ever I consider moving to a different bank. Never thought I'll get ****** by my own ban****!!!!!!!!!!!!