对'；使用SMTP PHPMailer；域'；电子邮件地址，已发送但未收到的电子邮件

我正在使用PHPMailer发送电子邮件。当我使用gmail smtp时，它工作得很好，但当我尝试使用我的域smtp时我在屏幕上看到的是"发送消息！"但我根本没有收到任何电子邮件。说："我试过使用调试器。"

We do not authorize the use of this system to transport unsolicited, 220 and/or bulk e-mail. 

这是我的代码

<?php
date_default_timezone_set('Etc/UTC');
//Load PHPMailer dependencies
require_once 'PHPMailerAutoload.php';
require_once 'class.phpmailer.php';
require_once 'class.smtp.php';
/* CONFIGURATION */
$crendentials = array(
    'email'     => 'xxxxx@example.com',    
    'password'  => 'xxxxxx'               
    );
$smtp = array(
'host' => 'secure.ehostpk.com',
'port' => 465,
'username' => $crendentials['email'],
'password' => $crendentials['password'],
'secure' => 'ssl' //SSL or TLS
);
/* TO, SUBJECT, CONTENT */
$to         = 'xxxxxx@example.com'; //The 'To' field
$subject    = 'This is a test email sent with PHPMailer';
$content    = 'This is the HTML message body <b>in bold!</b>';

$mailer = new PHPMailer();
//SMTP Configuration
$mailer->isSMTP();
$mailer->SMTPDebug  = 2;
$mailer->SMTPAuth   = true; //We need to authenticate
$mailer->Host       = $smtp['host'];
$mailer->Port       = $smtp['port'];
$mailer->Username   = $smtp['username'];
$mailer->Password   = $smtp['password'];
$mailer->SMTPSecure = $smtp['secure']; 
//Now, send mail :
//From - To :
$mailer->From       = $crendentials['email'];
$mailer->FromName   = 'Team'; //Optional
$mailer->addAddress($to);  // Add a recipient
//Subject - Body :
$mailer->Subject        = $subject;
$mailer->Body           = $content;
$mailer->isHTML(true); //Mail body contains HTML tags
//Check if mail is sent :
if(!$mailer->send()) {
    echo 'Error sending mail : ' . $mailer->ErrorInfo;
} else {
    echo 'Message sent !';
}

我找了很多，不知道该怎么办。如果有任何帮助，我将不胜感激。