You'd be amazed by the high number of people who are legally dead and how hard it makes the lives of them and their families. Literally no legal framework is properly prepared to acknowledge mistaken death cases and reinstating the legal personhood of someone declared legally dead. There's a story of one of them in India who formed an association of dead people, and got up to weird shenanigans to try and pressure the courts to declare him alive again. Including organizing and assisting to his own funeral, suing the state for his wife widower pension, getting himself arrested to force authorities to produce papers, and running for a local office election. There's a movie about him called, Kaagaz (2021). And he won an IgNobel price for his efforts to make mistaken death more visible.
Man was dead for almost 20 years, but he got better.