That sounds an awful lot like I bug I've experienced when playing Subnautica on linux through both steam's proton and regular wine. Any chance you are on linux? If so, one workaround in the Subnautica version was to alt-tab out and back into the game whenever it starts doing that; however in some cases that would cause the mouse pointer to be locked in the center of the screen when attempting to interact with menus -- another alt-tab toggles to the mouse-works-in-menus-but-not-for-camera mode. In the regular wine attempt, I was able to seemingly eliminate this issue by enabling wine's virtual desktop emulation (set to the same dimensions as my monitor's native resolution), but for some reason that didn't work in proton.

If I'm wrong and you aren't using wine, sorry for the useless information. :) Good luck with your problem!