Calibre has WiFi modules?
I don't think so.

Calibre relies on the OS to provide connectivity via the Network..
Look to your Server ends Firewall.
Look at you Device ends WiFi BAND or Network IP

IMHO 'Servers' should be on WIRED network connections. There
can be all sorts of additional WiFi access point security settings needed for 'Peer' type connections. (the better quality the network, the tighter the security it provides )

Read the CC FAQ pages about connectivity