Delay in closing a deceased person's account

Our estate attorneys have been trying to close my late father in law's accounts with ABSA for over 6 months and keep being told there is a backlog. This is holding up the whole process of winding up his estate and causing my mother in law undue stress.

I don't understand what the hold up is. I could walk in and close my account quite easily, so I don't see the difference if the attorney comes with all the documentation, death certificate, letter of executorship etc why it is taking so long!