Warning: require(vendor/autoload.php): failed to open stream: No such file or directory in C:\xampp\htdocs\booking\phpfile\PHPMailer\get_oauth_token.php on line 18

Fatal error: require(): Failed opening required 'vendor/autoload.php' (include_path='C:\xampp\php\PEAR') in C:\xampp\htdocs\booking\phpfile\PHPMailer\get_oauth_token.php on line 18