FNB fiduciary

I am not happy with FNB fiduciary. I have asked them to renounce as executors because the process is too slow and I am not working, I am having major problems and I cannot do anything because they are relaxed about the whole issue. I need to get the letter of executorship and they are driving me up and down refusing still to renounce. They don't care about my time and they are quiet. I am the one who always have to push them. I am studying and I don't have anyone both my parents passed and now FNB fiduciary is failing to renounce so that I can channel my life and get everything that is left by my parents for me. I have told them that I want them to renounce because I do not have money to pay them as I am not working but studying and now they are giving me hard time.