Hello,
I’m sorry to hear that you are facing issues with your main sitemap, category sitemap, and landing pages sitemap not showing up correctly. The error message you mentioned, “Incorrect http header content-type: ‘text/html; charset=UTF-8’ (expected: ‘application/xml’),” indicates a problem with the content type of your sitemap.
To resolve this issue, you can follow these steps:
-
Flush Permalinks:
- Navigate to your WordPress Dashboard → Settings → Permalinks.
- Click the “Save Changes” button without making any changes to flush the permalinks.

-
Flush Sitemap Settings in Rank Math:
- Go to Rank Math SEO → Sitemap Settings in your WordPress admin area.
- Change the value in the “Links Per Sitemap” field. If it is 200, change it to 201 or any other value.
- Click the “Save Changes” button at the bottom of the page.


After following these steps, please validate your sitemap again using an external tool like Validate XML Sitemap to ensure that the issue has been resolved.
If the issue persists, please reply to this ticket, and a human agent from our support team will assist you further.
Thank you for your understanding and patience.
Sources:
Rank Math Sitemap Issues and Their Fixes » Rank Math
How to Fix “Incorrect HTTP Header Content-Type” Error in Sitemaps » Rank Math
Indexed, Not Submitted in Sitemap – Google Search Console » Rank Math
Troubleshooting the “Couldn’t Fetch” Error in Google Search Console » Rank Math
I’ll try every basic instruction your bot robot provided but still it’s not working. I use validate xml sitemap to check my website and it shows like this:-Incorrect http header content-type: “text/html; charset=UTF-8” (expected: “application/xml”)
it is showing this error while validating xml sitemap of main and category sitemap and landing pages sitemap
Hello,
Thank you for contacting Rank Math support.
We have responded to your other ticket here – you can reply over there as well. We are closing this one in favor of that one.
Thank you for choosing Rank Math