Issue Observed:
Recently, I encountered an issue where multiple HTTPS entries were appearing in the sitemap.
Solution:
The fix was straightforward. The problem was due to an incorrect setting under:
Site /sitecore/content/Site/Settings/Site Grouping/Site1
Target Hostname:
The issue was resolved by removing the https
from the target hostname.
With this adjustment, the sitemap no longer displayed multiple HTTPS entries.