Instagram API：服务器无法接收数据

Question

我使用此代码从Instagram API获取数据。代码在某些服务器上正确运行，但在其他服务器上，它不会从Instagram API接收数据。所有服务器都启用了“Curl”，谁知道发生了什么？

<?php
require 'instagram.class.php';
require 'config.php';

// Receive OAuth code parameter
$code = $_GET['code'];

// Check whether the user has granted access
if (true === isset($code)) {

  // Receive OAuth token object
  // Take a look at the API response
  $data = $instagram->getOAuthToken($code);

  if(empty($data->user->username)){
    header('Location: index.php');
  } else {
    session_start();
    $_SESSION['xxx']=$data;
    $user=$data->user->username;
    $ig_id=$data->user->id;

    header('Location: profile.php');
  }

} else {
  // Check whether an error occurred
  if (true === isset($_GET['error'])){
    echo $_GET['error_description'];
  }
}
?>