Ring Elite No Longer Connecting to Network

I'm with a home automation/ integration company.I installed a Ring Elite a while back for my customer. It's been working just fine and powered via POE. It recently has lost connection with the network. I've verifed that the POE is working fine and in fact tried a backup unit. The network connection is also working just fine. I even verified all the cabling and POE power supplies. The unit will power up based on the fact the indicator light is lit up around the doorbell button (light blue). However, if you look at the indicator light at the network switch the POE is getting it's feed from, the port shows no activity. As if nothing is plugged into the network port. I've taken the unit off site for a closer look. It's exhibiting the same behaviour on completely different network switch and POE injector. I've tried several times to reset and redoing the setup. With the iphone app, I get as far as "Ring wants to join wi-fi network "Ring Setup 4e"?, however my phone fails to join network after many repeated attempts. It's as if the Ring doorbell isn't broadcasting an SSID during this stage of setup. While in this state, I can see no activity on the network switch providing a LAN connection to POE. If I perform a network IP scan, the Ring doesn't show up. Is this unit faulty?