PHP Failure on Form

Question

Apologies, I'm mostly self taught. I'm using the following code live on https://www.poadvisory.com/contact.html and the contact form appears to be working, ReCaptcha as well, but the email never comes. I've spent countless times on the phone with my hosting provider and they claim is a code issue and not a server issue. Surely it's something obvious I don't see. If anyone can help, I'd really appreciate it. I've searched the current questions but don't believe this is a duplicate question.

<?php
require('recaptcha-master/src/autoload.php');


$sendTo = 'Contact Form < my email goes here>';

$subject = 'New message from contact form';

$fields = array('name' => 'Name', 'surname' => 'Surname', 'phone' => 'Phone', 'email' => 'Email', 'message' => 'Message');

$okMessage = 'Contact form successfully submitted. Thank you, We will get back to you soon!';

$errorMessage = 'There was an error while submitting the form. Please try again later';


$recaptchaSecret = 'removed';


error_reporting(E_ALL & ~E_NOTICE);

try {
    if (!empty($_POST)) {

        
        if (!isset($_POST['g-recaptcha-response'])) {
            throw new \Exception('ReCaptcha is not set.');
        }
        
        $recaptcha = new \ReCaptcha\ReCaptcha($recaptchaSecret, new \ReCaptcha\RequestMethod\CurlPost());
        
        
        $response = $recaptcha->verify($_POST['g-recaptcha-response'], $_SERVER['REMOTE_ADDR']);

        if (!$response->isSuccess()) {
            throw new \Exception('ReCaptcha was not validated.');
        }
        
        
        $emailText = "You have a new message from your contact form\n=============================\n";

        foreach ($_POST as $key => $value) {
            if (isset($fields[$key])) {
                $emailText .= "$fields[$key]: $value\n";
            }
        }
    
        $headers = array('Content-Type: text/plain; charset="UTF-8";',
            'From: ' . $from,
            'Reply-To: ' . $from,
            'Return-Path: ' . $from,
        );
        
        mail($sendTo, $subject, $emailText, implode("\n", $headers));

        $responseArray = array('type' => 'success', 'message' => $okMessage);
    }
} catch (\Exception $e) {
    $responseArray = array('type' => 'danger', 'message' => $e->getMessage());
}

if (!empty($_SERVER['HTTP_X_REQUESTED_WITH']) && strtolower($_SERVER['HTTP_X_REQUESTED_WITH']) == 'xmlhttprequest') {
    $encoded = json_encode($responseArray);

    header('Content-Type: application/json');

    echo $encoded;
} else {
    echo $responseArray['message'];
}