Pascom server doesn't autoconfigure Grandstream endpoint

We have installed the latest Pascom server, and no matter what we try, it wont provision our Grandstream GXP1625 endpoint. We tried to enable DHCP on server, then connecting the phone directly to the server. We tried to let the router give IP to the phone, plugged the phone into the LAN, then the PC into the pc port. Still no succes.
We factory resetted the phone as this tutorial says ( but still no succes. Pascom documents says that the phone should be appear automatically under Devices, but its not even working, when im adding manually.
We tried to configure the phone itself, but still no succes.

Please give us some hint, what to look for, what to configure and where. Every PBX nowaday supports autoprovision. Should it work out-of-the-box?

Thanks in advance!

Doesn’t matter if the DHCP is on the server or on the router, the phone gets its IP adress always.

We can ping it from the server. As far as i know every config should be done through the web gui, but i cant find settings regarding Provisioning, or SIP config.

Have you tried to configure your DHCP server properly?

A hint is found in /de/ documentation only, not /en/.