Unable to pay my late mothers investment money

Old mutual is make the run around regarding the payment of the investment for my mother. Master of Court have issued a Letter Authority indicating the person who is authorized to deal with my late mothers money, since I went to one of the Old Mutual Offices in Forest Hill I did not get any joy cause they said Head Office is refusing to make payment as they will only pay to the Estate Account of Mrs Matane, and my late Mother did not have such account hence we went the Master of High Court route. Could you please Help as my siblings need that money.