Can't interact with anything in game view

I’m working on a menu with several buttons and input fields. For a while everything was working fine, but suddenly every button and input field is not reacting to being clicked on, as if everything’s been disabled. This problem is only occurring in one of my scenes. My canvas has a graphic raycaster and my buttons have methods attached to them.

Switching my UI assets to a new canvas fixed the issue, but I’m still not sure why that was necessary. The new canvas is identical to the old in the inspector.

In case someone else finds this. I ran into the same issue and it’s because I accidentally deleted the Event System that populates when you add an Canvas to the scene.