It's a copy of an existing cameras IP address? Meaning, you have 2 of the same display ports from 1 camera.
If you add the same camera (same ip address), you must use a different name. It will have an '*' after it. I noticed this on 2 cameras I did this too. I did this to make it easier to see the different zone alerts in the timeline (different color cameras). This can also be done for using AOI - which is awsome!