Avoid the "inner monologue" trap for too long. Give them something to do:
Memories don't usually just pop up for no reason. Pick a catalyst: A minor head injury or a fever dream. 1 : I Recalled the Memories of My Past Life...
High-pitched ringing or a blur of images (subway trains, office lights, a hospital bed). Avoid the "inner monologue" trap for too long
"Why is there no plumbing?" or "Wait, is that magic?" 1 : I Recalled the Memories of My Past Life...
Seeing an object that looks exactly like something from Earth (a toy, a book, or a specific tool).
"I remember why I died... and the person who killed me is in this room."