Linksys RT31P2 fails to register with server

This adapter was working for the previous few years, but suddenly failed to register with voipo service few days ago.
I submitted a support ticket, but always get the same copy & paste response (power cycle network, disable firewall, etc...) that doesn't really help.
I tried to connect a PC directly to the LAN port of the adapter. I can ping the device, but cannot access the configuration page.
Any help is appreciated.

After a hard reset of the adapter, and getting information from support on how to resync the device with voipo.
I am able to use the phone service again. Thank you.