Correct, but you can run
vcgencmd get_camera instead. You should get
1 for both supported and detected. If supported = 0 for some reason, run
sudo raspi-config and enabled it under interface options.
If detected = 0, then the system isn't seeing the camera at all, and that needs to be fixed before anything else.
edit: it sounds like this was working at one point though, so this isn't likely a physical connection issue or anything, but it probably wouldn't hurt to make sure the ribbon cables are plugged in snug.