fps is exactly half refresh rate.

So I am developing a vr game on unity and having hard time to optimize my vr game. When I test the game on pc I get solid 72fps, but when I test it on quest 2 fps is staying at exactly 36fps. Game still feels running smooth and refresh rate is 72fps. So I think it could not be coincidence that fps is exactly half refresh rate. So anyone has any idea of some setting I could have on?