Game Preview not working

Hi, this is the problem when i open unity and first time i click play the level is working but when it goes on the next one the buttons in my game are not clickable, then when i stop the game preview and play again none button is working again, just the first time i click play after opening unity in the first level buttons are working(no matter which level it is, it only works the first time i open unity then when it switches to another level buttons are unclickable again). Last i did was messing around in preferences and clicked on tizen sdk location and made its default to be in sdk folder. Please help im pissed with this, my game is done and i can publish it any moment and now i cant coz of this...