Power loss or not sure

[shaids]

Hi, I am experiencing video loss in a new installation am actually working on. One of the IP cameras (HIKVISION DS-2CD2T42WD-I8 BULLET) have exceeded 100 meters plus away from the NVR (HIKVISION DS-7608NI-E2/8PNVR). The NVR has builtin POE. Now When I first connect that specific IP camera, it worked fine. After 3 days or so, it stopped detecting the cameras but network lights behind the nvr are lite and blinking fine. I checked the cables with a lan tester and its okay. I am considering getting a poe booster/extender and trying it hoping there is loss of power.

Has anyone experienced this and what are my options here?