FNB ACCOUNT OF MY LATE HUSBAND

My husband passed away in Nov 2016. His account is still open even though it has been frozen. The reason for this is that i must keep it open until SARS closes his estate and pay the last money owed to him into his account. My problem however is that FNB has been charging bank cost of R185 per month, on this account which has not been active for over a year now. Their is a credit in this account but no transactions has been done so i do not understand what they are charging for, and they can not explain this to me either. They only say that this is the way it is. I would think if anything, the money (credit) in this account should urn some interest, not decrease by R185 per month. My husband was a client of FNB for more than 50 year so if you could please look into this matter for me i would appreciate it very much. The bank can not privide me with a year statement, only 3 months. Please see attached bank statement Thank you Mrs R van der Bank