What system are you playing on? Are you playing the game via the itch app? Have you tried to download an older save to see if it's an error in the save file? (You might be able to use the auto-saves in slot 19 and 20) Else, if it's not a bug in the save file but with the game files, you could try to re-download the full game and copy&paste the entire save folder from the www/save folder of the old game version to the new game version.
