Help - Internal network port forwarding problem

Hi!
I have new ipfire core 159 installation with RED and GREEN interfaces. GREEN network is 192.168.0.0/23 (base network, ipfire LAN ip 192.168.0.254). Green interface is connected to unmanageable switch. To this switch is also another network 192.168.11.0/24 (backup network) connected. I can configure Ipfire (by adding second IP address 192.168.11.254 to GREEN interface as gateway/DNS for backup network) so backup network has access to internet, but i need to forward internal port 192.168.11.254:2714 to dedicated IP:22714 on intenet cloud server. When i set up forwarding with ipfire GUI, ipfire logs allowed connections to 192.168.11.254:2714 but no forwarding is made and no logs about blocked packets in forward chain. Tested similar rule to forward 192.168.0.254:2714 to same internet cloud server port 22714 - works without problems.
Where is the problem?