Unprofessional

My Gran has been to Standard Bank 3 times already to closed my late mothers accounts and still has not received letters stating that the accounts are paid in full and closed which she was told by a consultant that they would be. When she goes to find out why they are still sending statements they tell her that they have not got any record that my mother has past away. Yet she has given them already 3 times all the documents that was required to close accounts yet they opened a late account for my late mother which my Gran has power over. My Gran has settled my mothers credit card and cheque account already and was told that they will close the accounts. Standard bank has been very unprofessional with trying to help her where she is the executive with letters from the Master Of The Court. When she went to Standard Bank again on Saturday the 23 January they politely tell her they have lost the documents. It is going on three months now and Standard Bank is delaying us from winding up my late mothers estate.