@crumblingbiscuit As @help wrote earlier, you have to set up a DNS record for your root domain (zahr.koeln) as well. Follow the instructions on the page Custom Domains. The relevant parts:

  • If you want to use a root domain such as yourdomain.com, create an "A" record wherever your domain is registered and use the IP address value: "".
  • If you want both the root domain and www.yourdomain.com to work, you'll need both an "A" record for the root domain and a "CNAME" record for the "www" version. You can enter either "yourdomain.com" or "www.yourdomain.com" in the Design page settings in Micro.blog.