I unzip the game and follow the instructions to play on my phone, but why does it say not supported?
There is two options.
1. You didnt installed renpy plugin for Joiplay from google play store.
2. You selected wrong file (be sure that it is the .exe one).
If none of this option is right for you, then try to redownload the game. Probably some files were damaged during download. Try to find more stable connection.