Dreaming of dead father dying again is a very strange dream and it is not rare. Many people see it. The meaning of the dream is that you are doing something wrong with your life. Your father is unhappy with your actions and he is showing it through his death.
The dream also means that you are in some kind of trouble and you need to be cautious about your actions. You should be careful while using vehicles or handling iron and fire.
Please note that the dream to have a meaning it should happen naturally. Thinking about the death of your father and then having the dream has no value.
It is good to visit a temple and offer prayers for your father so that his soul rests in peace.