(hate to ask this but i was having a similar issue and missed the obvious solution) have you tried deleting your save file from within the in-game menu on startup?
i rly hope you get to play this (if u havent already solved ur problem)!! honestly its a huge mystery where the save file is, i spent a good half an hour looking through recent files 😔
(edit, your pc should have a 'hummingwarp' folder somewhere, the save files in there!)