Domain isn't actually your domain.. its the access point domain from your users (based on the IP lookup):
https://experienceleague.adobe.com/docs/analytics/components/dimensions/domain.html?lang=en
If you want to capture your domain (as in you have a global suite with multiple domains), you will need to send that information into a dimension like server, or set up a custom domain (or if you have a custom dimension storing the URL, you could also use a Classification Rule using Regex to extract the domain from the URL)