Thanks in advance dor any help.

My site is with hostinger and the front end is fine, however when the contact form is filled out and button pushed i get a Http 500 Error.

This is the PHP code, spoke with hostinger and changed the details for the server still the same. Any Ideas.

<?php
use PHPMailerPHPMailerPHPMailer;
use PHPMailerPHPMailerSMTP;
use PHPMailerPHPMailerException;

require "vendor/autoload.php";

if(isset($_POST["Submit"])){
        
    $name = $_POST["fullname"];
    $email = $_POST["email"];
    $mobile = $_POST["phone"];
    $subject = $_POST["subject"];
    $message = $_POST["message"];

    $mail = new PHPMailer(true);

    // $mail->SMTPDebug = SMTP::DEBUG_SERVER;

    $mail->isSMTP();
    $mail->SMTPAuth = true;

    $mail->Host = "smtp.gmail.com";
    $mail->SMTPSecure = PHPMailer::ENCRYPTION_STARTTLS;
    $mail->Port = 587;

    $mail->SMTPSecure = 'ssl';
    $mail->SMTPSecure = 'tls';
    $mail->isHTML(true); 

    $mail->Username = "[email protected]";
    $mail->Password = "Arsenal@#2004";

    $mail->setFrom($email, $name);
    $mail->addAddress("[email protected]", "Envitics");

    $mail->Subject = "Inquiry from SEOHunt";
    $mail->Body = "Name : $name <br> Email : $email <br> Phone Number : $mobile <br> Subject : $subject <br> Message : $message";
    

    $secret = "6LfYBfcpAAAAAEykcY3Q3FiJ2T5vVCM2y-kYxPZF";
    
    // Empty response
    $response = null;
    
    // Check if the form was submitted
    if ($_POST["g-recaptcha-response"]) {
        $response = $_POST["g-recaptcha-response"];
    }
    
    // Verify the reCAPTCHA response
    if ($response != null) {
        $url = 'https://www.google.com/recaptcha/api/siteverify';
        $data = array(
            'secret' => $secret,
            'response' => $response
        );
    
        $options = array(
            'http' => array(
                'header' => "Content-type: application/x-www-form-urlencodedrn",
                'method' => 'POST',
                'content' => http_build_query($data)
            )
        );
        $context = stream_context_create($options);
        $result = file_get_contents($url, false, $context);
        $json = json_decode($result);
        if ($json->success) {
            $mail->send();
            echo '<script>alert("Mail sent successfully."); window.location.href = "index.html";</script>';
        } else {
            // reCAPTCHA verification failed
            echo '<script>alert("Error in Google reCAPTACHA"); window.location.href = "index.html";</script>';
        }
    } else {
        echo '<script>alert("No response for reCAPTCHA"); window.location.href = "index.html";</script>';
    }

}

Error Message.

atal error: Uncaught PHPMailerPHPMailerException: SMTP Error: Could not authenticate. in /home/u979039019/domains/seohunt.co.uk/public_html/vendor/phpmailer/phpmailer/src/PHPMailer.php:2265 Stack trace: #0 /home/u979039019/domains/seohunt.co.uk/public_html/vendor/phpmailer/phpmailer/src/PHPMailer.php(2062): PHPMailerPHPMailerPHPMailer->smtpConnect() #1 /home/u979039019/domains/seohunt.co.uk/public_html/vendor/phpmailer/phpmailer/src/PHPMailer.php(1689): PHPMailerPHPMailerPHPMailer->smtpSend() #2 /home/u979039019/domains/seohunt.co.uk/public_html/vendor/phpmailer/phpmailer/src/PHPMailer.php(1523): PHPMailerPHPMailerPHPMailer->postSend() #3 /home/u979039019/domains/seohunt.co.uk/public_html/form.php(70): PHPMailerPHPMailerPHPMailer->send() #4 {main} thrown in /home/u979039019/domains/seohunt.co.uk/public_html/vendor/phpmailer/phpmailer/src/PHPMailer.php on line 2265