FNB REVOVING FACILITY

I have a revolving facility with FNB, and the loan was in arrears , however the arrears were cleared, and the facility is still blocked unable to utilize the funds in it. I made a mistake on the 27 December and transferred R600 into the RCF and unable to reverse back the funds due to the hard hold on the account. I have tried to contact FNB and i am being taken from pillar to post. No one is able to assist me in this regard. I need the R600 that was transferred in error as there funds were for something else. FNB please assist in reversing the funds back to my cheque account.