It will sound funny, but first try restarting the computer, the computer may have been working for a long time and the cache has accumulated. And so. And also check the integrity of the files in the properties, and if it's the screen, try to delete the entire folder with the game and download it again, incomprehensible problems are sometimes solved elementary, but I say right away that it may not help, although it looks like if you run it a couple of times it should work, since I had something like that with full-screen mode