As far as I'm aware I just bought the game and didn't add an email. I could be wrong though.
You need to put in an email address when you buy it. Try searching back through your emails.
Try checking here as well: https://itch.io/my-collections
You need to put in an email address when you buy it. Try searching back through your emails.
Try checking here as well: https://itch.io/my-collections