Toubleshooting POE Camera

My Ring POE Camera was working great, and suddenly quit working. Here’s what I have done to date, with no results: 1- Confirmed that the camera has power - The blue light will flash when button pushed for setup mode. 2- Tried repeatedly to set it up and the app tells me it can’t connect to the internet. 3- Deleted the camera from my Ring network and tried to add it to the network and initialize it again. - no success. 4- Used an Ethernet cable check tool to check the cables from the router to the POE Adapter, and from the POE Adapter to the camera. Both checked good. 5- Switched the Ethernet cable to a different port in the router. I confirmed that the port I switched to has connectivity. I know the POE Adapter is sending power to the camera, because of the blue light on the camera. Also the light on the adapter is green. If I check the POE adapter with my Ethernet cable check tool I get a fault. This happens with the adapter plugged or unplugged to the electric power outlet. I do not know if this means the adapter is bad (no Ethernet continuity) or my check tool is not designed to check continuity through a POE Adapter. How do I determine if the camera has failed or the POE Adapter has failed (I do not have another POE adapter to swap in)? What are my next steps?