I am trying to install Traefik as an Ingress Controller for my self-installed Kubernetes cluster. For convenience I try to install the helm chart of Traefik and this works excellent without the acme part; this is my variables yml now:

externalIP: xxx.xxx.xx.xxx
dashboard:
  enabled: true
  domain: traefik-ui.example.com
ssl:
  enabled: true
  enforced: true
acme:
  enabled: true
  challengeType: http-01
  email: example@gmail.com
  staging: true
  persistence.enabled: true
  logging: true

Installed with:

helm install --name traefik --namespace kube-traefik --values traefik-variables.yml stable/traefik

But with helm status traefik I can see the v1/PersistentVolumeClaim named traefik-acme stays pending and the certificate is never assigned.