3CX SBC behind XG 125 - full clone test on 5060 failed

Hi everyone,

we would like to use a 3CX Session Border Controller behind a XG 125 with SFOS 18.5.1 MR-1-Build326.

I think I have created the firewall and NAT rules correctly, unfortunately the firewall check from 3CX reports on port 5060 the full clone test fails.

Also checked the log and don't see any UDP flood or something like that. The SIP module is unloaded.

3CX SBC is 192.167.27.2 (praxis-3cx) in zone VOIP and the Public IP is #Port7:0.

Meanwhile, i don't see problem, so I'll send you a few screenshots of the configuration and I'm grateful for any help.

Defined services:

Rules:

NAT:

Log:

3CX:

Port Query: