Refusal to close business CHEQUE account by FNB

I called the FNB business desk to close my account on 17 October 2017.At the end of the call I was told that I would receive an e-mail within three days confirming that the account had been closed.After three days, I still had not received the email, so I called FN business desk again. I was informed that due to the fact that there is a positive balance on my account as well as e-buck rewards, I will not be able to close that account over the phone and that I would have to go to the branch. I went to one of their branches on Friday the 20th but I was told that I can close the account but would not be able to withdraw my balance as the bank is about to close and that I should come back on the 21st before 11am. I went back today and the account still could not be closed. FNB wants me, in addition to the positive balance on my account, to pay an amount towards the monthly charges, which has already been deducted from my account on the 15th of October before they can close the account.