Connection error :SQLSTATE[HY000] [2002] Connection refused
Warning: Undefined variable $pdo in /var/www/html/header.php on line 11

Fatal error: Uncaught Error: Call to a member function prepare() on null in /var/www/html/header.php:11 Stack trace: #0 /var/www/html/page.php(2): require_once() #1 {main} thrown in /var/www/html/header.php on line 11