Problem obtaining ACME certificate for domain

I have a problem with requesting a SSL certificate for my domain:

Normally I only request SSL certificates for subdomains: and that works great.

What I wish to accomplish is that my website is reachable from and

For that, I added two A Records in my DNS management:
@ and www, both pointing to the correct IP.

However when I start up my container, Traefik is only able to create a certificate for, but not

I get the following error:

time="2022-01-14T09:16:35+01:00" level=error msg="Unable to obtain ACME certificate for domains ",": unable to generate a certificate for the domains []: error: one or more domains had a problem:\n[] acme: error: 403 :: urn:ietf:params:acme:error:unauthorized :: Invalid response from [IPv6 address]: "\n\n404 Not Found\n\n

Not Found

\n<p"\n" providerName=letsencrypt.acme routerName=app@docker rule="Host(,"


version: '3.7'

      context: ./
      dockerfile: Dockerfile
    command: gunicorn app.wsgi:application --bind --timeout 0
      - 8001
      - proxy
      - "traefik.enable=true"
      - ""
      - ""
      - "``,``)"
      - ""

    external: true

I thought the problem was the [IPv6 address], so I deleted all the AAAA Records. But that doesn't explain why the worked, right..? I did a check at and they couldn't find any AAAA records.

Why can I only create a certificate for, but not Am I missing DNS records?