For us, it was due to the driver station (the classmate driver station wouldn’t show camera feed, but the driver station on a different computer did get a camera feed.)
We concluded that our classmate probably was missing an update. We found the update somewhere on first. We used the update, but unfortunately it seemed not to have affected our drive station.
We ended up un-installing the driver station software and re-installing it, and then the camera feed started working.
This is how we resolved our problem, but you might have a different one.