Hello,
Thank you for your query and we are so sorry about the trouble this must have caused.
To ensure that Rank Math is generating the sitemap for GD, please head over to your WordPress > Rank Math > Sitemap Settings > [select the post type] and enable the option “Include in Sitemap”:

If the issue persists, please follow the steps below:
1. Flush the Sitemap cache by following this video screencast:
https://i.rankmath.com/pipRDp
2. Exclude the Sitemap files of the Rank Math plugin in your caching plugin. The cache could be via a plugin or from the server. For plugins or Cloudflare, please follow this article:
https://rankmath.com/kb/exclude-sitemaps-from-caching/
Hope that helps and please do not hesitate to let us know if you need my assistance with anything else.
Hey Jeremy,
Thanks for that, it was what I assumed it was but it still isn’t working. Is there a way to manually add URL’s to a sitemap?
Hello,
Here’s a filter on how to manually add URLs to sitemap: https://rankmath.com/kb/filters-hooks-api-developer/#add-extra-urls-in-sitemap
You may refer to this guide on how to add filters to your website: https://rankmath.com/kb/wordpress-hooks-actions-filters/
However, Rank Math should have added the sitemap automatically.
Please add the filter code to your theme’s functions.php file and see how it goes:
add_filter( 'rank_math/sitemap/enable_caching', '__return_false');
If the issue persists, you may come back to us here and we will assist you further.
Thank you.
Hello,
Since we did not hear back from you for 15 days, we are assuming that you found the solution. We are closing this support ticket.
If you still need assistance or any other help, please feel free to open a new support ticket, and we will be more than happy to assist.
Thank you.