Authorization not found In Php 8

Authorization not found when using below code in php 8 (xampp), it working in php 7(xampp)

Undefined Authorization key.

require "../vendor_big/autoload.php";
use \Firebase\JWT\JWT;
header("Access-Control-Allow-Origin: *");
header("Content-Type: application/json; charset=UTF-8");
header("Access-Control-Allow-Methods: POST");
header("Access-Control-Max-Age: 3600");
header("Access-Control-Allow-Headers: Content-Type, Access-Control-Allow-Headers, Authorization, X-Requested-With");
require $_SERVER['DOCUMENT_ROOT'].'/db.php';

$data = (json_decode(file_get_contents("php://input"), true));
$authHeader = apache_request_headers();
// print_r($authHeader);
$secret_key = "bmR0di1zYWxlcy1hcHAtYWR0ZWNoLXJpc2hp";
$jwt = null;
$arr = explode(" ", $authHeader["Authorization"]);
$jwt = $arr[1];

output

Array
(
    [Host] => localhost:8080
    [Connection] => keep-alive
    [sec-ch-ua] => " Not;A Brand";v="99", "Google Chrome";v="97", "Chromium";v="97"
    [sec-ch-ua-mobile] => ?0
    [sec-ch-ua-platform] => "Windows"
    [Upgrade-Insecure-Requests] => 1
    [User-Agent] => Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/97.0.4692.99 Safari/537.36
    [Accept] => text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,image/apng,*/*;q=0.8,application/signed-exchange;v=b3;q=0.9
    [Sec-Fetch-Site] => none
    [Sec-Fetch-Mode] => navigate
    [Sec-Fetch-User] => ?1
    [Sec-Fetch-Dest] => document
    [Accept-Encoding] => gzip, deflate, br
    [Accept-Language] => en-US,en;q=0.9
)

how to get authorization?