Sometimes when I start TD my facetime webcam only reads as unavailable, the iPhone camera only reads as unavailable, or both are unavailable. It doesn’t seem consistent and I think it’s likely not a TD issue but something else grabbing the camera feed, but I’m having trouble figuring that out.
This is usually always another app holding the device on you, often a video coferencing app like Zoom or Google Meet. The good news is you can use Mac’s Control Center to determine which apps are using cameras and microphones. Click on the control center and around the top it will list the apps using the camera. At least in macOS 15 it does, not sure if this was around in macOS 14…