SoundCloud API错误“请求的URL以HTTP代码401响应。”

The issue is i continually get a 401 error on the $client->accessToken($_GET['code']) step despite $_GET['code'] being set properly.

    require_once 'Services/Soundcloud.php';

    // create client object with app credentials
    define("CLIENT_ID","*****************");
    define("CLIENT_SECRET","*****************");
    define("REDIRECT_URL","********************");

    $client = new Services_Soundcloud(CLIENT_ID, CLIENT_SECRET, REDIRECT_URL);

    //redirect user to authorize URL
    $authURL =  $client->getAuthorizeUrl(array('scope'=>'non-expiring'));
    $client->setDevelopment(false);
    $code =  $_GET['code'];
    try {
        if(!isset($_SESSION['token'])){
          $code                 =   $_GET['code'];  
          $access_token         =   $client->accessToken($code);   
          $_SESSION['token']    =   $access_token['access_token'];
        }else{
          $client->setAccessToken($_SESSION['token']);  
        }
    } catch (Services_Soundcloud_Invalid_Http_Response_Code_Exception $e) {
        echo $e->getMessage();
    }

Getting The requested URL responded with HTTP code 401

Any help is greatly appreciated.