unv ip camera show red light continously and not working

[lisatag652 0]

I have poe switch 8 port, 4 camera working and 4  unv ip camera show red light continously also not working. IN our POE switch power and data light showing but in nvr it does not working it show network disconnected. 

when i directly connected UNV POE switch to my laptop it show only 4 camera out of 8  in EZ station UNV software . I have changed rj45 connector and test lab cable pair ok, also change camera but it not working and show red light continuously on .

please tell me what is the problem and give me solution