WordPress中高级自定义字段的分类

Question

I have the below code which creates a taxonomy like its supposed to and updates the post field with the value the first time around. But when i have 2 posts that need the same taxonomy, the code does not insert it.

$make_term = get_term( $make, 'car_make' );

    if (!empty($make_term)) {
        wp_set_object_terms($post_id, $make_term['term_taxonomy_id'], 'car_make');
    } else {
        $make_tax = wp_insert_term($make, 'car_make');
        if ( ! is_wp_error( $make_tax ) && ! empty( $make_tax['term_taxonomy_id'] ) ) {
            wp_set_object_terms($post_id, $make_tax['term_taxonomy_id'], 'car_make');
        }
    }

Does anyone have any ideas please?