Rancher - Traefik Netcup ACME

Hello,

I'm currently setting up a new server and facing some issues with acme dns auth.

Traefik is setted up as an app inside Rancher. The DNS authentication are provided as secrets.

The Traefik pod now returns the following:

{"level":"error","msg":"Unable to obtain ACME certificate for domains "traefik.My-Domain.de" detected thanks to rule "Host:traefik.My-Domain.de" : cannot get ACME client netcup: some credentials information are missing: NETCUP_CUSTOMER_NUMBER,NETCUP_API_KEY,NETCUP_API_PASSWORD","time":"2021-02-15T16:59:02Z"}

Does anyone knows a solution for that error?

My secret:

ACME App Config:

acme: 
    enabled: true
    email: "MAIL"
    onHostRule: true
    staging: true
    logging: true
    challengeType: "dns-01"
    dnsProvider:
      name: "netcup"
      existingSecretName: "netcup-dns"