SMTP problems using IIS and PHPMailer - php

Question

So i have been working on a proyect using PHPMailer for a while now and after doing a bunch of testing it works perfectly fine on my localhost. But now im facing a problem, because when i try to submit my form in the live server (i'm using IIS on a Windows 10 PC and PHP 5.6 ), it won't even load anything and skips me directly to the "Message has been sent" page, which is very strange because i have seen lots of posts where people say they receive an error message, but for some reason my PHPMailer code seems to be completely ignored. PHP does work on my proyect because there is a login page working so i really don't know what to do at this point.
I have tried looking for the SMTP Virtual Server option on IIS but i don't seem to find it.
I have tried disabling $mail->IsSMTP(); and nothing happens.
Here is my code:
<?php
use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\Exception;
require '/PHPMailer/Exception.php';
require '/PHPMailer/PHPMailer.php';
require '/PHPMailer/SMTP.php';
require_once __DIR__ . '/vendor/autoload.php';
$mail = new PHPMailer(true);
try {
//Server settings
$mail->SMTPDebug = 1;
$mail->isSMTP();
$mail->Host = 'mail.domain.com'; // Set the SMTP server to send through
$mail->SMTPAuth = true; // Enable SMTP authentication
$mail->Username = 'email#mycompany.com'; // SMTP username
$mail->Password = 'password'; // SMTP password
$mail->SMTPSecure = 'tls'; // Enable TLS encryption; `PHPMailer::ENCRYPTION_SMTPS` also accepted
$mail->Port = 587; // TCP port to connect to
$mail->SMTPOptions = array(
'ssl' => array(
'verify_peer' => false,
'verify_peer_name' => false,
'allow_self_signed' => true
)
);
//Recipients
$mail->setFrom('email#mycompany.com', $);
$mail->addAddress('email#mycompany.com'); // Add a recipient
$mail->addStringAttachment('stuff');
// Content
$mail->isHTML(true); // Set email format to HTML
//$mail->Subject = $;
//$mail->Body = $;
$mail->Subject = '';
$mail->Body = '';
$mail->CharSet = 'UTF-8';
$mail->send();
echo '<script> alert (".");
windows.history.go(-1);</script>';
} catch (Exception $e) {
echo "";
}
?>
I tried using this code too for testing but it echoed "not ok".
<?php
if(mail('user#mydomain.com','test subject','test message')){
echo('ok');
}
else{
echo('not ok');
}
?>
Thanks in advance.