Do other Itch app games work? I haven't heard of this issue being specific to my game.
It might need to be reinstalled. Your saves will be fine if you uninstall the game.
The only suggestion I can think of is to play the game without the app. Download it separately. Does an error pop up or does the game just not start? If the game just doesn't start it is very hard to know exactly what the problem is, because it's not an error that happens for me. Sorry, it's very hard to test.