You will need to factory reset the camera. While it’s connected. The little black button inside the little compartment. Hold down for 30 seconds.
Do not unplug it. Do not screw with any settings. After resetting it, wait, wait some more, then hit the refresh button at bottom of that NVR camera screen and it will turn green (if it doesn’t all on its own)
What is the exact model number of this camera?