problem in sitemap validation created by rankmath

Hello,

I apologize for the issue you are facing with your sitemap validation after switching from SEOPress to Rank Math. The error message “Incorrect HTTP header content-type: ‘text/html’ (expected: ‘application/xml’)” indicates that the server is not serving the sitemap with the correct content type.

To resolve this issue, you can follow the steps below:

1. Flush Permalinks:

   • Navigate to WordPress Dashboard → Settings → Permalinks.
   • Click the Save Changes button without making any changes to flush the permalinks.

2. Flush Sitemap Settings:

   • Go to Rank Math SEO → Sitemap Settings in your WordPress admin area.
   • Adjust the value in the Links Per Sitemap field and save changes. If the option is unavailable, switch to Advanced Mode in Rank Math.

3. Exclude Sitemap from Caching:

   • If you have caching enabled, exclude the sitemap from being cached. You can refer to this tutorial for detailed instructions.

4. Check Restrictions from Web Host:

   • Ensure that there are no restrictions on sitemap access by your web host or security plugins. If needed, exclude the sitemap from firewalls or security measures.

If the above steps do not resolve the issue, you can also add a filter to your theme’s functions.php file as mentioned in this guide.

After implementing these solutions, please validate your sitemap again. If the problem persists or you need further assistance, feel free to reach out to our support team directly here. We are here to help.

Thank you for bringing this to our attention. Let us know if you need any more help.

Best regards.

Sources:
How to Fix “Incorrect HTTP Header Content-Type” Error in Sitemaps » Rank Math
Rank Math Sitemap Issues and Their Fixes » Rank Math