SMTP Error: Could not connect to SMTP host.

Hello,
I have a problem connecting to SMTP with PhpMailer. It's throwing me this error:

SMTP Error: Could not connect to SMTP host. Connection failed. stream_socket_enable_crypto(): SSL operation failed with code 1. OpenSSL Error messages:error:14090086:SSL routines:ssl3_get_server_certificate:certificate verify failed

Link to script: https://yaperfumy.pl/mail.php

Code: [Select]

<?php
use PHPMailer\PHPMailer\PHPMailer;
use PHPMailer\PHPMailer\SMTP;
use PHPMailer\PHPMailer\Exception;

require_once __DIR__ . '/vendor/phpmailer/phpmailer/src/Exception.php';
require_once __DIR__ . '/vendor/phpmailer/phpmailer/src/PHPMailer.php';
require_once __DIR__ . '/vendor/phpmailer/phpmailer/src/SMTP.php';

$mail = new PHPMailer(true);
$mail->SMTPDebug = 1;
$mail->isSMTP();
$mail->Host = 'mail.yaperfumy.pl';
$mail->SMTPAuth = true;
$mail->Username = "test@yaperfumy.pl";
$mail->Password = "password";
$mail->SMTPSecure = "tls";
$mail->Port = 587;

$mail->From = "test@yaperfumy.pl";
$mail->FromName = "Full Name";

$mail->addAddress("lesniewski.jakub94@gmail.com", "recipient name");

$mail->isHTML(true);

$mail->Subject = "Mail sent from php send mail script.";
$mail->Body = "<i>Text content from send mail.</i>";
$mail->AltBody = "This is the plain text version of the email content";

try {
    $mail->send();
    echo "Message has been sent successfully";
} catch (Exception $e) {
    echo "Mailer Error: " . $mail->ErrorInfo;
}
?>

Contact your hosting privider

Allot of providers have PHP Mail disabled for security.
(block the users to be able to send spam emails or infected emails from php mail function.)

If you have root access, then you can enable it.

You might have to contact your upstream also to make sure all the SMTP ports are open.