Identity Unknown

This is an Apple Books audiobook narrated by a digital voice based on a human narrator.
MISSING MEMORIES 

When a John Doe washes up on the shores of Calico Bay, no one knows who he is—including him. But one thing's instantly clear to deputy sheriff Audrey Martin: the man's marked for murder. And she's the only one who can protect him from the assassins who lurk at every turn. The arrival of a team of men claiming he's Canadian Border Services officer Nathanial Longhorn only further complicates the matter. As his memories slowly start drifting back, Nathanial's determined to work with Audrey to uncover who wants him dead and why. But he's tangled in something that threatens to submerge them both. And unless Audrey can help him figure out what, this Christmas might be their last.