Hello,
Thank you for contacting Rank Math, and sorry for any inconvenience that might have been caused due to that.
A noindex
robots meta tag is added to the sitemap on purpose. This is in line with Google’s guidelines and that is how sitemaps work.
Please submit your sitemap_index.xml file to Google Search Console so Google can see all URLs in your sitemap.
Exclude the Sitemap files of the Rank Math plugin in your caching plugin. The cache could be via a plugin or from the server.
https://rankmath.com/kb/exclude-sitemaps-from-caching/
I hope this helps you with your issues.
Hello,
We are super happy that your issue is resolved. If you have any other questions in the future, know that we are here to help you.
If you don’t mind me asking, could you please leave us a review (if you haven’t already) on https://wordpress.org/support/plugin/seo-by-rank-math/reviews/#new-post about your overall experience with Rank Math? We appreciate your time and patience.
If you do have another question in the future, please feel free to create a new forum topic, and it will be our pleasure to assist you again.
Thank you.