Problem with license synchronization - Synchronization with server failed (Device not found)

I've got a problem with my XG Firewall.
It cannot connect to a license server. I can't use any of the advanced features because of that.
In "tail -f /log/licensing.log" it says that "Device not found", and "Problem with the local SSL certificate".
I recently reseted it to default settings, but it still is not able to contact license server.
I don't know what should I do.