Make query parameter an endpoint

You need to put this code into your product single page before get_header() function start.

<?php
global $wp;
if( isset($_SERVER['QUERY_STRING']) && isset($_GET['order']) ){
    $url = home_url( $wp->request . '/order/' );
    wp_safe_redirect( $url );
    exit;
}
?>

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)