PHP issue can not run notie

I’m trying to run notie in my PHP Code but it does not working for me.

<?php

/* ******************************************************** */
/* Please visit the help file to set correctly this file :) */
/* ******************************************************** */

// Set to "mailchimp" or "file"
$STORE_MODE = "mailchimp";

// MailChimp API Key findable in your Mailchimp's dashboard
$API_KEY =  "";

// MailChimp List ID  findable in your Mailchimp's dashboard
$LIST_ID =  "";

// After $_SERVER["DOCUMENT_ROOT"]." , write the path to your .txt to save the emails of the subscribers
$STORE_FILE = $_SERVER["DOCUMENT_ROOT"]."/subscription-list.txt";

/* ************************************ */
// Don't forget to check the path below
/* ************************************ */

require('MailChimp.php');

/* ***************************************************** */
// For the part below, no interventions are required
/* ***************************************************** */
if($_SERVER["REQUEST_METHOD"] == "POST" && !empty($_POST["email"])) {
	$email = $_POST["email"];
	header('HTTP/1.1 200 OK');
	header('Status: 200 OK');
	header("Content-Type: text/html");

	// Checking if the email writing is good
	if(filter_var($email, FILTER_VALIDATE_EMAIL)) {

		// The part for the storage in a .txt
		if ($STORE_MODE == "file") {

			// SUCCESS SENDING
			if(@file_put_contents($STORE_FILE, strtolower($email)."\r\n", FILE_APPEND)) {

			// ERROR SENDING
			} else {
			}

		// The part for the storage in Mailchimp
		} elseif ($STORE_MODE == "mailchimp") {

			$MailChimp = new \Drewm\MailChimp($API_KEY);

			$result = $MailChimp->call('lists/subscribe', array(
		                'id'                => $LIST_ID,
		                'email'             => array('email'=>$email),
		                'double_optin'      => true,
		                'update_existing'   => true,
		                'replace_interests' => false,
		                'send_welcome'      => false,
		            ));

			// SUCCESS SENDING
			if($result["email"] == $email) {

			// ERROR SENDING
			} else {

			}
		// ERROR
		} else {

		}
	// ERROR DURING THE VALIDATION
	} else {

	}
} else {
	header('HTTP/1.1 403 Forbidden');
	header('Status: 403 Forbidden');
}

echo '<link defer href="https://unpkg.com/notie/dist/notie.min.css" rel="stylesheet">';
echo '<script defer src="../../vendors/jquery/jquery-3.1.1.min.js"></script>';
echo '<script defer src="https://unpkg.com/notie"></script>';
echo '<script defer>
window.notie.alert({ type: "success", text: "Success!", time: 1.5 })
</script>
';

?>

[jaredreich]

Ok, that makes much more sense, thanks. I will investigate.

[BilalReffas]

     ¯\_(ツ)_/¯