Heimdall & Traefik

Hi all, I am hoping you can help. I have a Hetzner dedicated server with Ubuntu 20.4, Docker & Portainer. I have Traefik as a reverse proxy and for the past week I have been trying to add a sub domain to Heimdall and failed. I have trawled the web and don’t seem to find anything that works, I just get the 404 error. It’s either to do with Labels or Ports. Can anyone assist please