Docker not working with caddy network default mode

[ghost]

Sorry for the cross-post but maybe this is the proper section for my problem. I'm self-hosting the docker image on localhost:8080 but it won't start and I get a "127.0.0.1:8080 IP already in use". If I delete the line "network_mode =host" the containers start successfully, but I don't know if and how caddy really works this way.