Doing "New Game" from the main menu has you do a fresh playthrough. But also checking the \AppData\Roaming\RenPy\CabinByTheLake
and deleting the save files in it can help
I've tried but the saves are still there and the file comes back, I don't know how to fully reset.
Evil got you very close, but the final part they missed was that you also need to delete the persistent file in the same location.