BeamNG REFUSES to enter fullscreen

So, recently, BeamNG has been giving me a lot of trouble trying to enter fullscreen mode. My monitor's (current) native resolution is 3200x1800. I'm trying to run BeamNG at 2560x1440 in fullscreen, as my system is on the medium side of things, and 3200x1800 lags my game quite a bit. Up until today, I had no problem doing this. But now, BeamNG REFUSES to enter full screen. I click the button. The game clearly *tries* to enter full screen, but next thing I know, the game is still running in windowed mode with the fullscreen box unchecked. Other times, the game enters windowed mode filling up my entire screen, with a 1440p box at the upper left, with the rest of the window pink and with the resolution the game thinks its it's running being 5k. (I use a mac that's been bootcamped to run Windows.) and then, other times, the window fills up my entire screen without glitching out, however, it'll still be in windowed mode. This is really weird, and I think it has something to do with V-sync, as these issues didnt start happening until I turned it on. Nothing out of the ordinary in the console, either.

 

I havent updated my drivers recently, and as for things that could display over the game, that would be the Steam Overlay, as I bought the Steam version of BeamNG. However, I've used the overlay plenty of times on BeamNG in the past with no negative effect. Probably just some weird glitch with Windows 10, or my video drivers. (which would be a pain to reinstall because AMD's support site is a mess) However, BeamNG finally decided to cooperate, as I managed to get the game to run in fullscreen at 1440p. I should probably close this thread now...