Accessing Containers from a different VLAN trough Traefik

I have a Server with Traefik on Docker set up and if I access all the Containers using the FQDN on the same Network(VLAN) as the docker Container and Client are located, all works. If I access it from a different VLAN, I can get to the Containers.

I try to TCPDump and get TCP retransmission error try to NAT on the Firewall and do exclude it from Nating, without success.

The Firewall Rules are set to pass all, so I don’t believe is a Firewall issue. I also try to ICMP and their seams all to be working fine from both VLAN. On the Dockerhost i try to setup custom Iptables without success.

Do you have an Idea where I can find the issue?