我得到了帖子，但它们不是按“排序”值排序的。以下代码有什么问题？

$args[\'meta_query\'] = array(
    \'relation\'  => \'AND\',
    \'cast\'      => array( 
        \'key\'       => \'cast\',
        \'value\'     => $cast, 
        \'compare\'   => \'LIKE\'
    ),
    \'director\'  => array(
        \'key\'       => \'director\',
        \'value\'     => $director,
        \'compare\'   =>\'=\'
    ),
    \'sort\'      => array(
        \'key\'       => \'score\',
        \'compare\'   =>\'EXISTS\'
    ) 
);
$args[\'orderby\'] = array( \'sort\' => \'DESC\' );