Lemmy Support

from the logs it seems that lemmy docker does not communicate with outside servers.

also i have a bit different config for lemmy.hjson

{
  # for more info about the config, check out the documentation
  # https://join-lemmy.org/docs/en/administration/configuration.html

  setup: {
    # username for the admin user
    admin_username: "adminuser"
    # password for the admin user
    admin_password: "adminpassword"
    # name of the site (can be changed later)
    site_name: "group.lt"
  }

  opentelemetry_url: "http://otel:4317"



  # the domain name of your instance (eg "lemmy.ml")
  hostname: "group.lt"
  # address where lemmy should listen for incoming requests
  bind: "0.0.0.0"
  # port where lemmy should listen for incoming requests
  port: 8536
  # settings related to the postgresql database
  # address where pictrs is available
pictrs: {
    url: "http://pictrs:8080/"
    # api_key: "API_KEY"
}
  database: {
    # name of the postgres database for lemmy
    database: "lemmy"
    # username to connect to postgres
    user: "lemmy"
    # password to connect to postgres
    password: "lemmy"
    # host where postgres is running
    host: "postgres"
    # port where postgres can be accessed
    port: 5432
    # maximum number of active sql connections
    pool_size: 5
  }
#  # optional: email sending configuration
  email: {
#    # hostname and port of the smtp server
    smtp_server: "postfix:25"
    smtp_from_address: "from@group.lt"
    tls_type: false
  }


}

also check in admin interface if federation is enabled and you do not blacklist instances

(https://lemmy.bulwarkob.com/admin) and maybe you can try to enable federation debug mode for awhile