Estates finalisation is dismall

Very dissatisfied with the assistance we have received from Nedgroup trust in finalising my mothers estate. It has been 6 months now and there has been absolutely no movement at all. I have been dealing with a lady called Mandisa Mngoma at *** and it has been very difficult to get hold of her and when we finally do get hold of her its always the same response that they are waiting for the Masters letter. How can we wait for a letter for 6 months!!!! We need assistance please!