WP Flush Rewrites 404 Permalink WordPress

<?php
function ds_flush_blogs_rewrite($blog) {
    global $wp_rewrite;

    switch_to_blog($blog);
    $wp_rewrite->flush_rules();
    restore_current_blog();
}

function update_siteurl() {
    global $wpdb;

    $sites = $wpdb->get_results($wpdb->prepare("SELECT * FROM $wpdb->blogs"));

    foreach ( $sites as $site ) {
        $id = $site->blog_id;
        ds_flush_blogs_rewrite($id);
        $url = get_site_url($site->blog_id);
        update_blog_option($id,'siteurl',$url);
        update_blog_option($id,'home',$url);
    }
}
?>