Mandao of the Dead (2018) on Netflix

Plot summary

Jay Mandao lives on the royalties from his late father's cereal and would rather be on his own. He is talked into letting his adult nephew-in-law, Jackson, stay at his place. Halloween is coming, and Jay keeps having strange dreams. He works out that he can leave his body and travel as a spirit, an ability he did not know he had. A ghost arrives with a request: he died at the hands of Jackson's ex-girlfriend, and that death can still be undone, but only inside a short window. Reversing it would mean Jay and Jackson going back as spirits to the moment it happened.