Hello, if you've been playing the game using Joiplay, we've received the report that the current version is no longer compatible with Joiplay's latest update.
The only solution for that is to wait for Joiplay to release a new update that's compatible with newer Renpy games. Otherwise, you can also try to play the demo through the Steam Link app if you have a Steam account. The last option would be to play this on your PC.
We do have an Android port on our development list, but that's still some time away. Many apologies for the inconveniences.