I have a problem with the build of my game. Buttons are not working after main menu in the build of the game (they work fine in the editor). They are not even highlighting. I've spent a few hours looking it up. no UI is above it.  the event system picks up the button in the editor.  the script works fine as i have used it in different games and it works in the editor.

The way I have it set up is:
↓Canvas
     Text
     Text
     ↓Panel - this panel turns on and off
          Text
          Text
          Button - these buttons are not working
          Button

the event system has the 'Event system' and the 'standalone input module'. 
I copied all the settings for the canvas over to the 

Sorry for the trouble I am still relatively new at game development.

I would still like to know why but because of time constraints I'm going for a no button design now.

I was having this issue with my game as well. This is the video I watched that fixed it for me: (Just so you know though, this video is about the Event System. Basically the idea is that in your main menu scene, you have an event system, but in your next scene, you forget to add an event system. I'm not entirely sure if you're saying that you already have an event system in each scene but just in case here's this video. )