Hi Phone is connected through stun and also run firewall check status is ok.You really haven't provided any useful information.
Is the set local to the PBX? If not, how is it connected...SBC, STUN? If not local, have you run the 3CX Firewall Checker, and did it pass?
Was it the 3CX Activity Log that you checked? If so and there was no log of an attempted registration, then, either the set is not registering to the correct FQDN, IP, and/or port, or something is blocking the attempt (IP blacklist, firewall, lack of port forwarding).
Since this is not a supported device we have not tested it so we can not provide information on how to register the device to 3CX. But since it works with the SBC why not use an SBC in each location? You could also try to register the device directly to the PBX and see if that works.I tested this handset with sbc, its working fine but the main problem is that I have globally multiple locations and pbx is hosted on google cloud so any way to provision Panasonic kxhdv 230.
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