In Game stuck in Windowed Mode

So I launched into a ranked game today and the screen resolution was immediately set into windowed mode. Even when I set it back to fullscreen it stays on half of my screen, it just displaces itself on the left side. I tried to change the resolution but there are no options under the header "resolution," all the options just appear blank and there is nothing to click on so it seems like there is no way for me to change it back to an actual full screen resolution Help pls D: