Solved: Low resolutions on different computers?

Question. I have a game that I built and tested on my Mac laptop and the resolution was 1680 x 1050, which is fine. Today I took the game on a jump drive to test it out on my friends 2016 27" iMac. When we launched the game it came up with the display options and the max resolution was 960 x y. Can’t remember exactly was the y was but was surprised that the resolution was so low on such a large screened and faster computer?

Why is this and how can I fix this?

Thanks.

Player settings only had 16:10 checked, not 16:9