The game is crashing after you play for 20-30 minutes plss fix it
Hard crashes like that are usually caused by the "Ren'py engine" itself, not working with your Android device, rather than the game code itself.
If the issue is because of the Ren'py Engine and it is some unknown bug that occurs with your device, then I cannot do much.
I've had a look through some Ren'py forums, and there looks like some Android fixes for the next version of the engine, but I'm not sure if this will fix your specific issue or not, when the next version of Ren'py is released.