/tag/feed/ URL of my website keeps getting indexed On Google

Hello,

Thank you for contacting Rank Math and bringing your concern to our attention. I’m sorry for any inconvenience this issue may have caused you.

We’ve checked your robots.txt, and the disallow rule for feed URL is not added there.

You should add the rule like this:

Disallow: */feed/

Moreover, if you want to completely disable them on your site, you can follow this guide:
https://kinsta.com/knowledgebase/wordpress-disable-rss-feed/

Hope that helps.

Thank you.

Hello,

You can add the following filter on your website to set the feed URLs to noindex:

add_action( 'template_redirect', 'noindex_feeds' );
function noindex_feeds() {
    if ( ! is_feed() ) {
        return;
    }
header( 'X-Robots-Tag: noindex', true );
}

Here’s how you can add filter/hook to your WordPress site: https://rankmath.com/kb/wordpress-hooks-actions-filters/

However, please note that when you set noindex to your feed URLs that means Google will not index them on SERPs, but Google will still be able to crawl those URLs. If you don’t want Google to crawl those URLs then you can add the following disallow rule to your robots.txt file.

Disallow: */feed/

Here’s a guide on how to edit your robots.txt using Rank Math:
https://rankmath.com/kb/how-to-edit-robots-txt-with-rank-math/

Once done, allow Google some time to re-crawl your site to reflect the changes.

Let us know how it goes. Looking forward to helping you.

Thank you.