cURL to PHP cURL

我在将cURL转换为PHP cURL时遇到了一个小问题。

cURL是：

curl -X POST https://api.curated.co/PUBLICATION_KEY/api/v1/email_subscribers -H 'Accept: application/json' -H 'Content-type: application/json' -H 'Authorization: Token token="API_KEY"' -d '{ "email" : "new_subscriber@example.com" }'

我正在将其转换为：

<?php 
$headers = array(
    'Accept: application/json',
    'Content-type: application/json',
    'Authorization: Token token="API_KEY"'
);
$data = array("email" => "new_subscriber@example.com");                                                                    
$data_string = json_encode($data);
$ch = curl_init('https://api.curated.co/PUBLICATION_KEY/api/v1/email_subscribers');                                                                      
curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "POST");                                                                     
curl_setopt($ch, CURLOPT_POSTFIELDS, $data_string);                                                                  
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);                                                                      
curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);       
$result = curl_exec($ch);
?>

但我没有得到任何回应。注意：我正在用正确的API_KEY和PUBLICATION_KEY进行更改。

我遵循本指南：http://support.curated.co/hc/en-us/articles/201753981-Adding-Subscribers-with-the-API

如果我遗漏了什么，你能告诉我吗？