PHPmailer scipt sending duplicate emails

Question

I have configured a twilio webhook for forwarding an sms message to my email. It is working, but for some reason I keep receiving duplicate emails. I have verified that the script is not being called twice, so there must be a problem with the script itself.

`<?php

ini_set('display_errors', 1);
ini_set('display_startup_errors', 1);
error_reporting(E_ALL);

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

// Load Composer's autoloader
require 'vendor/autoload.php';

// Twilio SMS webhook handling
$body = $_POST['Body'] ?? '';
$from = $_POST['From'] ?? '';
$to = $_POST['To'] ?? '';

if (!empty($body) && !empty($from)) {
    // Forward SMS to email
    forwardSmsToEmail($from, $body, $to);
}

function forwardSmsToEmail($sender, $message, $recipient) {
    $mail = new PHPMailer(true);

    try {
        //Server settings
        $mail->isSMTP();
        $mail->Host = '127.0.0.1';
        $mail->SMTPAuth = true;
        $mail->Username = 'email';
        $mail->Password = 'password';
        $mail->SMTPSecure = 'ssl'; // or 'ssl'
        $mail->Port = 1025; // or 465 for SSL
        $mail->SMTPOptions = [
  'ssl' => [
    'verify_peer' => false,
    'verify_peer_name' => false,
    'allow_self_signed' => true
  ]
];


        //Sender and recipient
        $mail->setFrom('Sender');
        $mail->addAddress('Recipient');

        //Content
        $mail->isHTML(false);
        $mail->Subject = "Text from $sender to $recipient";
        $mail->Body = "$message";
        $mail->SMTPDebug = 3;
        $mail->send();
        echo 'Message has been sent';
    } catch (Exception $e) {
        echo "Message could not be sent. Mailer Error: {$mail->ErrorInfo}";
    }
}