It is common to see a person in their dreams die and still be scared by the incident when they wake up. If a dream is mostly just about one specific dying the symbolic meaning may come from that person’s insecurity about the act itself. For example, seeing oneself die may point to feelings of inadequacy or lack of control about their realities.
In dreams, die signifies the end of story and its meaning will be lost. It could also by means of interruption or stoppage, or a catastrophe. They all signify an impending devastating event which needs to be stopped to find a way for someone to attain ultimate peace in their final rest.
The sudden death could symbolize stopping something which is not yet complete whereas a major catastrophe signifies that it’s just too late for someone’s life spiral downwards and the final rest may mean atonement.