Network unavailable

[si.org]

Dear forum,

i write for support on an Ip phone yealink cp960. We are trying to connect it to our LAN as if it were a normal Desktop PC by assigning a static IP address to the device, but the device is unable to communicate.
Show "network unavailable" message.
From the cable where we are trying to connect it, I tried to connect a desktop pc and this connects to the network without problems.

Even trying to ping the yealink, we obtain time out answer.

It seems a little bit tricky to set up, i supposed it was a simple configuration like a Desktop...
Another things, i can view only the Microsft teams splash screen and its settings,
and from these settings i set the Ip address, subnet mask.

Can you help me set it up?

Regards.