Configuration de phpmail

Bonjour j'ai configuré phpmail et on navigateur ma envoyer l'erreur
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Fatal error: Uncaught Error: Undefined constant "PHPMailer\PHPMailer\FILTER_FLAG_HOST_REQUIRED" in C:\xampp\htdocs\ecommerce c\vendor\phpmailer\phpmailer\src\PHPMailer.php:3599 Stack trace: #0 C:\xampp\htdocs\ecommerce c\vendor\phpmailer\phpmailer\src\PHPMailer.php(3565): PHPMailer\PHPMailer\PHPMailer::isValidHost('localhost') #1 C:\xampp\htdocs\ecommerce c\vendor\phpmailer\phpmailer\src\PHPMailer.php(2304): PHPMailer\PHPMailer\PHPMailer->serverHostname() #2 C:\xampp\htdocs\ecommerce c\vendor\phpmailer\phpmailer\src\PHPMailer.php(1421): PHPMailer\PHPMailer\PHPMailer->createHeader() #3 C:\xampp\htdocs\ecommerce c\vendor\phpmailer\phpmailer\src\PHPMailer.php(1316): PHPMailer\PHPMailer\PHPMailer->preSend() #4 C:\xampp\htdocs\ecommerce c\register.php(89): PHPMailer\PHPMailer\PHPMailer->send() #5 {main} thrown in C:\xampp\htdocs\ecommerce c\vendor\phpmailer\phpmailer\src\PHPMailer.php on line 3599" et je sais pas quoi faire et j'ai besoin d'aide