php - Apple Push notifications working sometimes but not always -

i using php in backend send apple push notification. receiving notifications not.

i know simple code use, if there other ways send notifications. cant understand why not delivering , does.

ps: using production build

function sendpush($user_id,$message,$video_id,$not_type,$devicetoken)  {  $passphrase = 'xxxxx';  $ctx = stream_context_create(); stream_context_set_option($ctx, 'ssl', 'local_cert', 'xxx.pem'); stream_context_set_option($ctx, 'ssl', 'passphrase', $passphrase);   $fp = stream_socket_client('ssl://gateway.push.apple.com:2195', $err, $errstr, 60, stream_client_persistent, $ctx);  if (!$fp)     exit("failed connect: $err $errstr" . php_eol);   $body['aps'] = array(         'alert' => $message,         'badge' => '1',         'sound' => 'default'); $body['payload'] = array(         'type' => $not_type,         'user_id' => $user_id,         'video_id' => $video_id     );        $payload = json_encode($body);       $msg = chr(0) . pack('n', 32) . pack('h*', $devicetoken) . pack('n', strlen($payload)) . $payload;       $result = fwrite($fp, $msg, strlen($msg));       if (!$result)         echo 'message not delivered' . php_eol;         else             echo 'message delivered' . php_eol;              fclose($fp);  } 

apple:

keep connections apns open across multiple notifications; don’t repeatedly open , close connections. apns treats rapid connection , disconnection denial-of-service attack. should leave connection open unless know idle extended period of time—for example, if send notifications users once day ok use new connection each day.