Camera isn't working

I checked that Chrome recognized the camera & did a test video.
I checked privacy & permissions, and Jitsi is allowed to use the camera.
I disconnected Skype.
Other participant’s cameras work.
I can join by phone O.K., but not laptop.

Also, I can share my screen still.

What are the results on test.webrtc.org?

I don’t know what that means. It looks like a website. I’ll go there.

This is what it said:

[ FAILED ] getUserMedia failed with error: NotReadableError

[ FAILED ] getUserMedia failed with error: NotReadableError

That shows your camera is not being detected. The website tests your system to make sure you can successfully connect to a webrtc videoconference.

So what do I do? It worked fine for a year.