I had the opportunity to install the original Google Pixel OS and re-install GrapheneOS on the phone, but the "camera in use" error was persistent across both operating systems, so it seems certain it is a hardware problem.
manuzetace Chopped7821 it happens to me, clear camera cache, I did it and it works
I addressed the option of force close, clear cache, and delete data previously:
Chopped7821 I tried that a while ago when I first got the message that my camera was being used
de0u Is it possible to provide links to cases involving new users?
I was referring to the problem persisting when I create a new user on the phone, not to other new users of GrapheneOS, however a google search reveals this is a problem for other Pixel users as well.
https://reddit.com/r/GooglePixel/comments/ujlhyp/cant_turn_on_flashlight_camera_in_use_but_i_didnt/
https://reddit.com/r/GooglePixel/comments/15bsajg/pixel_7_pro_flashtorch_not_working/
https://www.ifixit.com/Answers/View/854137/Flashlight+says+%22camera+in+use%22
The phone's camera can still be used, only it says "flash/torch is unavailable for this mode".