Yeah, I've got this multiple times now from others as well. So basicly back then I couldn't do the resolution setting so it's just 1920x1080.
I could probably fix this with my current knowledge, but the game was made on a really old unity version so I'm not really able to fix that.
But I highly suggest for you to check out the current game I'm working on, RawPoly Battlegrounds. Although it's still in alpha stage, there are a lot of stuff that it's already better at compared to RawPoly FPS!