Same slug on custom post type and hierarchical taxonomy

Hello,

I have a Custom Post Type and a Hierarchical Taxonomy.

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With a post_type_link filter I can achieve the following URL structures:
mysite.com/eskuvoi-ruhaszalon/category1/product-name1
mysite.com/eskuvoi-ruhaszalon/category1/subcategory1/product-name1

function filter_post_type_link($link, $post) {
    if ($post->post_type != 'wedding_salon') return $link;
    if ($cats = get_the_terms($post->ID, 'salon_location')) $link = str_replace('%salon_location%', array_pop($cats)->slug, $link);
    return $link;
}
add_filter('post_type_link', 'filter_post_type_link', 10, 2);

But taxonomy subcategory pages return with 404 error. I can only access subcategories without hierarchical structure.

mysite.com/eskuvoi-ruhaszalon/category1/subcategory1 – doesn’t work 404
mysite.com/eskuvoi-ruhaszalon/subcategory1 – it works

Do you have any idea how can I fix hierarchical taxonomy URL structure in this case?