考虑一下创建自定义文章类型的时候是否没有写：
‘map_meta_cap’ => true, ？
示例代码段如下：

<?php
add_action('init', 'flam_Blog');

function flam_Blog()
{
    $labels = array(
        'name' => 'Blog Post',
        'singular_name' => 'Blog Post',
        'menu_name' => 'Blog Post',
        'name_admin_bar' => 'Blog Post',
        'add_new' => 'Add Blog Post',
        'add_new_item' => 'Add New Blog Post',
        'new_item' => 'New Blog Post',
        'edit_item' => 'Edit Blog Post',
        'view_item' => 'View Blog Post',
        'all_items' => 'All Blog Post',
        'search_items' => 'Search Blog Post',
        'parent_item_colon' => 'Parent Blog Post',
        'not_found' => 'No Blog Post found',
        'not_found_in_trash' => 'No Blog Post found in trash',
    );
    $args = array(
        'labels' => $labels,
        'description' => 'Blog Post',
        'public' => true,
        'publicly_queryable' => true,
        'show_ui' => true,
        'show_in_menu' => true,
        'query_var' => true,
        'rewrite' => array('slug' => 'blog'),
        'capability_type' => array('blog','blogs'),        
        'has_archive' => true,
        'show_in_rest' => true,
        'hierarchical' => true,
        'menu_position' => 5,
        'supports' => array('title', 'editor', 'thumbnail'),
        'map_meta_cap' => true,
    );
    register_post_type('blog', $args);

    register_taxonomy('blog-tax', 'blog', array(
        'label' => __('Blog Category'),
        'rewrite' => array('slug' => 'blog-tax'),
        'hierarchical' => true,
        'show_in_rest' => true,
        'show_ui'           => true,
        'show_admin_column' => true,
        'query_var'         => true,
        'map_meta_cap' => true,
    )
    );
}