Game crashed after enabling 29 button at the same time

Hi guys. I just make a alphabet game and I have to create a 29 button for each letters. So, when i press " play" button 29 buttons should be appear. But game crashed and shut down itself. These all happening on the phones, not on the editor. I can not understand.Why phones cant handle just 29 button ?

@agackarakas have you tried with just 10 or so? that way you can see whether or not the buttons are the problem