Appalling service from Old Mutual executors

I am writing on behalf of my elderly mother

My Moms sister passed away last year in august naming Old Mutual as executors . There has been an appalling lack of communication from Old Mutual regarding the winding up of the estate . There has been no direct communication with the beneficiaries informing them of what assets are in the estate . The beneficiaries are all in their mid 80s and are anxious to have the estate finalised but emailed communication receives no response and when trying to call their is either no answer or excuses given such as the person dealing with it is off sick etc . There is a total lack of empathy and lack of willingness to assist