Suddenly our VOIP phones stopped working a few months ago and since then I am trying to bring them back online. I even brought another technician and he couldn’t do anything because he didn’t know about FreePBX.
The issue I am having is that phones lost their SIP registration.
We are using Grandstream 1620 phones. I rebooted them, I updated the firmware but I still get the Network Down message on the phone screen.
Our PBX is running on Elastix 4.0
I would really appreciate your help!