Почему не работает meta_query ACF?

global $post;
$status = $_POST['status'] ? $_POST['status'] : '';

// var_dump($status); 
// array(3) { [0]=> string(7) "instock" [1]=> string(4) "sold" [2]=> string(8) "intheway" }

$cars = new WP_Query([
'post_type' => $post_type,
'post_status' => 'publish',
'meta_query' => [
               [
                   'key'     => 'position_car',
                   'value'   => $status,
                   'compare' => 'NOT IN',
               ],
        ]
 ]);

// show
if ($cars->have_posts()):
while ($cars->have_posts()): $cars->the_post();

  the_title();

endwhile;
endif;

wp_reset_postdata();
wp_die();