PHPMailer不起作用但没有错误，smtpdebug设置为2

Question

I have gone through multiple questions like this and nothing seems to fix my problem. I have set the SMTP debug option to 2, checked my credentials (changed to example ones for posting obviously) also checked the smtp server and port, using gmail and tls with port 465. I'm using ajax to submit form data on the click on submit button.

<?php

use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\Exception;

/* Exception class. */
require '/home/saveyamo/public_html/PHPMailer/src/Exception.php';

/* The main PHPMailer class. */
require '/home/saveyamo/public_html/PHPMailer/src/PHPMailer.php';

/* SMTP class, needed if you want to use SMTP. */
require '/home/saveyamo/public_html/PHPMailer/src/SMTP.php';


$errorMSG = "";


/* NAME */

if (empty($_POST["firstName"])) {
    $errorMSG = "<li class='danger'>Your first name is required</<li>";
} elseif (!filter_var($_POST["firstName"], FILTER_VALIDATE_INT) === false) {
    $errorMSG = "<li class='danger'>A number is not a valid name</<li>";
} else {
    $firstname = filter_var($_POST["firstName"], FILTER_SANITIZE_STRING);
}

if (empty($_POST["lastName"])) {
    $errorMSG = "<li class='danger'>Your last name is required</<li>";
} elseif (!filter_var($_POST["lastName"], FILTER_VALIDATE_INT) === false) {
    $errorMSG = "<li class='danger'>A number is not a valid name</<li>";
} else {
    $lastname = filter_var($_POST["lastName"], FILTER_SANITIZE_STRING);
}


/* EMAIL */

if (empty($_POST["email"])) {
    $errorMSG .= "<li class='danger'>Email is required</li>";
} elseif (!filter_var($_POST["email"], FILTER_VALIDATE_EMAIL)) {
    $errorMSG .= "<li class='danger'>Invalid email format</li>";
} else {
    $email = $_POST["email"];
}

/*phone*/
/*
if (empty($_POST["phone"])) {

    $errorMSG = "<li>Your phone number is required</<li>";

} else if (is_string($_POST["phone"])) {

  $errorMSG = "<li>That is not a valid phone number</<li>";

} else if (is_int($_POST["phone"])) {

    $phone = $_POST["phone"];

}
*/

function validate_phone_number($phones)
{
    // Allow +, - and . in phone number
    $filtered_phone_number = filter_var($phones, FILTER_SANITIZE_NUMBER_INT);
    // Remove "-" from number
    $phone_to_check = str_replace("-", "", $filtered_phone_number);
    // Check the lenght of number
    // This can be customized if you want phone number from a specific country
    if (strlen($phone_to_check) < 10 || strlen($phone_to_check) > 14) {
        return false;
    } else {
        return true;
    }
}

if (validate_phone_number($_POST["phone"]) == true) {
    $phone = $_POST["phone"];
} elseif (validate_phone_number($_POST["phone"]) == false) {
    $errorMSG = "<li class='danger'>That is not a valid phone number, try again. Be sure to include your area code.</li>";
} elseif (empty($_POST["phone"])) {
    $errorMSG = "<li class='danger'>Your phone number is required</<li>";
}



/* marina */

if (empty($_POST["marina"])) {
    $errorMSG = "<li class='danger'>Your marina is required</<li>";
} else {
    $marina = filter_var($_POST["marina"], FILTER_SANITIZE_STRING);
}

/* checkboxes */

$boxes = $_POST["boxes"];


/* MESSAGE */

if (empty($_POST["message"])) {
    $errorMSG .= "<li class='danger'>Message is required</li>";
} else {
    $message = filter_var($_POST["message"], FILTER_SANITIZE_STRING);
}


if (empty($errorMSG)) {
    $message = "Name: ".$firstname." ".$lastname."<br />".", Email: ".$email."<br />".", Phone: ".$phone."<br />".", Marina: ".$marina."<br />".", Interests: ".$boxes."<br />".", Message:".$message;
    $ok = "<li class='ok'>Awesome! Your message was sent, we will be in touch shortly.</li>";
    //echo json_encode(['code'=>200, 'msg'=>$message]);
    echo json_encode(['code'=>200, 'msg'=>$ok]);

    $to = "[e-mail]";
    $subject = "Contact";

    //mail($to, $subject, $message);
    //phpmailer start

    $mail = new PHPMailer(true);                              // Passing `true` enables exceptions
    try {
        //Server settings
    $mail->SMTPDebug = 2;                                 // Enable verbose debug output
    $mail->isSMTP();                                      // Set mailer to use SMTP
    $mail->Host = 'smtp.example.com';  // Specify main and backup SMTP servers
    $mail->SMTPAuth = true;                               // Enable SMTP authentication
    $mail->Username = '[e-mail]';                 // 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('[e-mail]', 'Contact Form');
        $mail->addAddress('[e-mail]');               // Name is optional
        $mail->addReplyTo('$email', '$firstname');

        //Content
    $mail->isHTML(true);                                  // Set email format to HTML
    $mail->Subject = 'Contact Form Submission';
        $mail->Body    = '$message';
        $mail->AltBody = 'This is the body in plain text for non-HTML mail clients';

        $mail->send();
    } catch (Exception $e) {
        echo 'Message could not be sent. Mailer Error: ', $mail->ErrorInfo;
    }

    //phpmailer end
    exit;
}


echo json_encode(['code'=>404, 'msg'=>$errorMSG]);