Hey @ShadowStrider2!
Hmm. When I run into issues like this (especially with behavior trees), the first thing I do is go to content> rightclick> fix up redirectors. Then I save all, close, restart my pc and try it again. USUALLY that works. Especially with the “Everything was fine before” context.
Give that a try and if that doesn’t work, let’s get some close-up screenshots of the code 
that video isn’t high enough rez to see the words on the screen.