Php脚本抛出错误请求错误

Question

我正在使用此代码使用Fowiz发送消息，但这是一个错误的请求错误BUt没有显示400.Any help please。

<?php
        $mypasscode = 'your passcode';
        $my_username = 'your fowiz username';    
        $to_phone_number = 'recipient phone number';
        $my_message = 'your message';

        $curl = curl_init();
        curl_setopt($curl, CURLOPT_URL, 
            "http://cloud.fowiz.com/api/message_http_api.php");
        curl_setopt($curl, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($curl, CURLOPT_POSTFIELDS, http_build_query(array(
            'username' => $my_username,
            'phonenumber' => $to_phone_number,
            'message' => $my_message,
            'passcode' => $my_passcode,
        ), '', '&'));        

        $result = curl_exec($curl);    
        $error = curl_error($curl);    
        curl_close($curl);    

        echo $result;
    ?>