<?php
ini_set('display_errors', 1);
error_reporting(E_ALL);
$username = "M_DE_NORDIC_VIT";
$password = "123456NC";

$url = "https://platform.trackbox.com/api/pull/customers";

$key = "264388973aaa9b2f9eb2aa84a9c7382e";

$jsonObj = array(
            'from' => '2018-01-01 00:00:00',
            'to' => '2018-01-31 00:00:00',
            'type' => '2'
            );

try{
        $curl = curl_init($url);



        curl_setopt_array($curl, array(
            CURLOPT_RETURNTRANSFER => 1,
            CURLOPT_POST => 1,
            CURLOPT_HTTPHEADER => array("x-trackbox-username:".$username, "x-trackbox-password:".$password, "x-api-key:".$key, "Content-type:application/json"),
            CURLOPT_POSTFIELDS => json_encode($jsonObj),
        ));
        $result = curl_exec($curl);

        if (FALSE === $result)
              throw new Exception(curl_error($curl), curl_errno($curl));

    }catch(Exception $e) {

      trigger_error(sprintf(
          'Curl failed with error #%d: %s',
          $e->getCode(), $e->getMessage()),
          E_USER_ERROR);

  }
        echo '<pre>';
        print_r($result);
 ?>