Traffic works on LAN but not WAN

I deployed Traefik on docker behind our OpenWRT router and I do not understand why the server replies to requests from the LAN with the URLs but not on the WAN. I deployed a dummy nginx server to make sure the router forwards the ports and the nginx server replies correctly on the ports from the WAN, but the Traefik server does not reply to any requests from the WAN. Has anyone seen this problem that could point me in the right direction? Thank you all.