When I previewed my scene, the camera where you can see it is stuck at the other end of the level, as it is not following the character and isn’t staying in the boundaries of the game. For this level I simply inserted a new sprite into the platformed template game and then the camera started to go outside the red boundaries and then started to glitch getting stuck at the edge of the screen and not moving.
That is not a bug with the engine but with your events. Please post a screenshot of your events for people to be able to help you find the source of the issue.
This is what it looks like when it gets stuck:
Before:
What was also extremely weird is the fact that it was working fine one day, and then when I went onto it around a day later and it wasn’t working, even though I had not changed anything. That is what made me think there was a bug in the system.