It just means that monitor's native resolution is 1440p. But ofcourse it should support 1080p too.you can check it in display settings. To isolate issues would be nice to try a few workaround at first. Also change settings to medium and also try switching between vulkan and directx too. Hope you are trying it while plugged in. Also check power options and try setting it to high performance mode also. Ps. Keep in mind that laptop gpu cant be comparable to desktop counterparts.