I don't get why it won't work for you. Is it failing on start up or not saving your progress?
It doesn't save my progress at shutdown. Everytime I start the game, I'm starting from beginning with 400 heartpoints, no purchases and nothing unlocked.
You mentioned to clear the cache and data in android app settings but that didn't work as well. Tried it on a different device, too. Same issue.
Why don't you code a save button into the game if autosave fails? 🤔 😅