traefik - BasicAuth

Problem: I wan't to implement basic Auth on some entrypoints (e. g.: Traefik Dashboard, Prometheus), but i can't get it to work

Context: I've got a bunch of Docker Containers running between a Traefik Proxy. (GitLab, Grafana, HomeAssistant, Prometheus, Min.IO, influxdb, jaeger etc.) and i want to make sure some of the Services are secured using Traefik' BasicAuth Middleware

traefik.yml

providers:
  docker:
    endpoint: "unix:///var/run/docker.sock"
    exposedByDefault: false
    watch: true

api:
  dashboard: true
  insecure: true

entryPoints:
  http:
    address: ":80"
  https:
    address: ":443"
  gitea-ssh:
    address: ":30022"
  traefik-metrics:
    address: ":8082"
  influx-db:
    address: ":8086"
  gitlab-ssh:
    address: ":11022"
  gitlab-metrics:
    address: ":11909"
  traefik:
    address: ":8080"

http:
  traefik:
    entrypoints: traefik
    middlwares:
      - "auth"

  middlewares:
    auth:
      basicAuth:
        users:
          - "<removed>"

global:
  checkNewVersion: true

metrics:
  prometheus:
    entryPoint: traefik-metrics
    addEntryPointsLabels: true
    addRoutersLabels: true
    addServicesLabels: true
    buckets:
      - 0.1
      - 0.3
      - 1.2
      - 5.0

tracing:
  jaeger:
    localAgentHostPort: <removed>
    samplingServerURL: <removed>

accessLog:
  filePath: "/var/log/traefik"

the middleware doesn't even show up in the traefik dashboard -> http -> middlwares

i'm not that experienced in traefik, so it would be great if someone could help me.