Camera is not working in any app

I've done every troubleshooting tip I can find, but I still cannot get my camera to work in any application, including facetime and Photo Booth. (My main need is to connect it to Zoom)

My OS and everything is presently up to date. I've restarted multiple times and made sure Zoom has permission to use the camera. I have also done the sudo killall VDCAssistant to no avail.

I tried to download the iSight Updater but my computer won't accept it.

Please offer any other options or advice