Hello,
Thank you for contacting Rank Math support, and sorry for any inconvenience that might have been caused due to that.
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/
If the issue persists, please share the post URL which is currently missing from the sitemap.
Looking forward to helping you on this one.
Hello,
I have updated the sensitive data as requested. Can you please check further?
Thank you.
Hello,
We might need to take a closer look at the settings. Please edit the first post on this ticket and include your WordPress & FTP logins in the designated Sensitive Data section.
Please do take a complete backup of your website before sharing the information with us.

It is completely secure and only our support staff has access to that section. If you want, you can use the below plugin to generate a temporary login URL to your website and share that with us instead:
https://wordpress.org/plugins/temporary-login-without-password/
You can use the above plugin in conjunction with the WP Security Audit Log to monitor what changes our staff might make on your website (if any):
https://wordpress.org/plugins/wp-security-audit-log/
We really look forward to helping you.
Hello,
I have updated the sensitive data as requested. Can you please check further?
Thank you.
Hello,
I noticed that your canonical tag has the current URL but without the trailing slash as you can see in my screenshot below:

I would like to check the affected post but when trying to open the editor, I got greeted with a critical error. Can you please verify that?
Please try checking the individual post under the “Advanced” tab in your SEO settings and ensure the Canonical field is left empty:

Let us know how that goes.
Hello,
I have updated the sensitive data as requested. Can you please check further?
Thank you.
I have deleted the rank-math.php file because the code was incorrect. Also, I have deleted the code to set no-cache in the .htaccess file in the rank-math plugin. The post is Now updated in the sitemap. Can you please help me out whether I have to re-write the code for no-cache in the .htaccess file in the rank-math Plugin?
What was the issue? I couldn’t locate it.
How can I avoid this type of error in the sitemap in the future so that post gets automatically updated in the sitemap? The post is updated in the sitemap.
Thanking you,
Regards,
Pradnya Gokhale
Hello,
The issue is due to a mismatched canonical URL to the current post URL.
I can confirm that it is now working on your end. I also tried adding a new post and it is added to the sitemap file right away.
Let us know if you encounter this issue again and if the sitemap isn’t updated, you may also let us know.
We are here to help you.
Thank you very much Rank Math Team for solving the issue of the sitemap. I must say you really have great support and your Team give prompt support to Free Account Users with equal importance. Looking forward to purchasing paid plugin from you.
Thanking You,
Regards,
Pradnya Gokhale
Hello,
We are super happy that this issue is already resolved. If you have any other questions in the future, know that we are here to help you.
If you don’t mind us 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 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.