wp_update_term_count_now doesn’t work with a custom post type?

I have a custom post type name session and a tag name post_tag.

This is the declaration of my custom post type :

function create_posttype()
{

  register_post_type(
    'session',
    array(
      'labels' => array(
        'name'                => __('Sessions'),
        'singular_name'       => __('Session'),
        'menu_name'           => __('Sessions'),
        'all_items'           => __('Toutes les sessions'),
        'view_item'           => __('Voir sessions'),
        'add_new'             => __('Ajouter'),
        'edit_item'           => __('Modifier'),
      ),
      'hierarchical'            => true,
      'public'                  => true,
      'show_in_rest'            => true,
      'supports'                => array('title', 'thumbnail', 'revisions, custom-fields'),
      'taxonomies'              => array('category', 'post_tag'),
      'menu_position'           => 20,
      'menu_icon'               => 'dashicons-groups',
    )
  );

}
add_action('init', 'create_posttype');

I need to add a tag, so i do this :

wp_set_post_tags($session->ID, "annule", false);

It works. But then i have a problem with my total of post type for this tags in the backend. So i do this :

$update_taxonomy = 'post_tag';
$get_terms_args = array('taxonomy' => $update_taxonomy,'hide_empty' => false);                      
$update_terms = get_terms($get_terms_args);
wp_update_term_count_now($update_terms,  $update_taxonomy);

But this doesn’t work.

I suppose i’m doing something wrong. But i don’t see what ?

Thanks