$mail = new PHPMailer(false); // Passing `true` enables exceptions

    //Server settings
    //$mail->SMTPDebug = 1;//Enable verbose debug output
    $mail->isSMTP();//Set mailer to use SMTP
    $mail->Host = 'smtp host';//Specify main and backup SMTP servers
    $mail->SMTPAuth = true;//Enable SMTP authentication
    $mail->Username = 'user';//SMTP username
    $mail->Password = 'password';//SMTP password
    $mail->SMTPSecure = 'tls';//Enable TLS encryption, `ssl` also accepted
    $mail->Port = 587;//TCP port to connect to


    //Recipients
    $mail->setFrom('example@example.com','myapp');
    $mail->addAddress('hi@examle.com');//Add a recipient
    //$mail->addAddress('ellen@example.com');//Name is optional
    $mail->addReplyTo('support@example.com','Contact');



    //Content
    $mail->isHTML(true);//Set email format to HTML
    $mail->Subject = 'test';

    $mail->Body    = 'this is a test';


    $mail->send();

$mail->isSMTP();//Set mailer to use SMTP
    $mail->Host = 'smtp host';//Specify main and backup SMTP servers
    $mail->SMTPAuth = true;//Enable SMTP authentication
    //Assuming SMTP_USERNAME is your environment variable which holds username
    $mail->Username = getenv('SMTP_USERNAME');
    //Assuming SMTP_PASSWORD is your environment variable which holds password
    $mail->Password = getenv('SMTP_PASSWORD');
    $mail->SMTPSecure = 'tls';//Enable TLS encryption, `ssl` also accepted
    $mail->Port = 587;//TCP port to connect to