Incorrect http header content-type: “” (expected: “application/xml”)

Hello,

Thank you for contacting us and we regret the inconvenience caused.

The post sitemap is loading properly on the website. However, I checked the robots.txt file and it does not have the sitemap URL.

Please add this statement at the end of the robots.txt file:
Sitemap: https://techtofeed.com/sitemap_index.xml

You can follow this guide to edit the robots.txt generated by Rank Math: https://rankmath.com/kb/how-to-edit-robots-txt-with-rank-math/

Also, I tested the variations of sitemap using https://httpstatus.io/ and found that 3 variations are returning 200 status.

Except for the preferred variation (which should return only a 200 status), all the non-preferred variations of the website should redirect to the preferred variation and return a 301 + 200 status.

Please follow the steps in this link:
https://rankmath.com/kb/couldnt-fetch-error-google-search-console/#5-check-for-the-correct-version-of-the-sitemap and redirect to the correct variation.

You can also get in touch with your web host regarding this.

Once this is fixed, please clear your website’s cache, remove all the sitemaps from your Google Search Console account, and then submit only the main sitemap: /sitemap_index.xml.

Further, give Google some time to crawl your website again and see if the issue gets fixed.

Hope this helps.

Thank you.