Problem with Curl or Json (Debian 7.2, PHP 5.5 e etc)

Hi, I have a site that is running Opencart and makes payment for the Paybras, testing locally worked 100%, but in Digital Ocean Json return of payment is always null. The Firewall is empty and already installed Curl and Json, etc-http://162.243.88.70/info.php. The code used is as follows:

$ch = curl_init ($url); $data _ string = json_encode ($data);

curl_setopt ($ch, CURLOPT_CUSTOMREQUEST, “POST”); curl_setopt ($ch, CURLOPT_POSTFIELDS, $data _ string); curl_setopt ($ch, CURLOPT_RETURNTRANSFER, true); curl_setopt ($ch, CURLOPT_HTTPHEADER, array ( ’ Content-Type: application/json ', ’ Content-Length: '. strlen ($data _ string)) ); $resultado = curl_exec ($ch); curl_close ($ch); return $resultado;

Log data: It returns the following steps: 2/3/2014 13:44:04-Paybras = 1 validation 2/3/2014 13:44:04-Calling the Curl Paybras 2/3/2014 13:44:05-Return the Json (wave) 2/3/2014 13:44:05-if non-success

Being the return of Json (Curl) was to return a variable of success, but as the return is empty does not return anything. The Curl is running normal with other mode of payment, so that’s not a problem with him. The function is called by Ajax Post type and Json data and before you go to the Log data is converted into PHP with json_decode and only after I test the Log. Does anyone have any idea what can be the problem?