How to fix bugs that only appear in the build?

I'm making an android game and i found a bug. I think it has something to do with PlayerPrefs. In the main menu you can buy an ability and if you change the scene, it should get through PlayerPrefs a value and show the button in the game. But it doesn't show the button. It only does, when i restart the game. In the editor everything works perfectly. How do i fix these kind of bugs?? Please help me