Breadcrumbs not working correctly on posts page.

Hello,

I apologize for the issue you are facing with the breadcrumbs on your posts page. To customize the breadcrumbs on your posts page to display the correct hierarchy like Home » Articles » Article, you can use a custom code snippet.

You can add the following filter to your site to include a ‘Blog’ page in the breadcrumbs and adjust the hierarchy accordingly:

/**
 * Filter to add a 'Blog' page to Rank Math Breadcrumbs.
 */
add_filter( 'rank_math/frontend/breadcrumb/items', function( $crumbs, $class ) {

    if ( is_home() || is_front_page() ) {
        return $crumbs;
    }

    $blog = ['Blog',
         'https://yourdomain.com/blog' //replace with the URL of your blog page
        ];
    if (count($crumbs) 

Sources:
How to Customize Breadcrumbs in Rank Math » Rank Math
How to Enable Breadcrumbs on Your Website With Rank Math SEO » Rank Math