diff --git a/HttpServer/Events/OnPacket.php b/HttpServer/Events/OnPacket.php
index 9a583940..0e7981f7 100644
--- a/HttpServer/Events/OnPacket.php
+++ b/HttpServer/Events/OnPacket.php
@@ -43,14 +43,10 @@ class OnPacket extends Callback
 			if (empty($data)) {
 				throw new Exception('Format error.');
 			}
-			$client = DataResolve::pack($this->pack, $data);
-			return $server->sendto($clientInfo['address'], $clientInfo['port'], $client ?? 'Format error');
+			return $server->sendto($clientInfo['address'], $clientInfo['port'], DataResolve::pack($this->pack, $data));
 		} catch (\Throwable $exception) {
-			$client = DataResolve::pack($this->pack, $exception->getMessage());
-
-			var_dump($exception->getMessage());
-
-			return $server->sendto($clientInfo['address'], $clientInfo['port'], $client ?? 'Format error');
+			$pack = DataResolve::pack($this->pack, ['message' => $exception->getMessage()]);
+			return $server->sendto($clientInfo['address'], $clientInfo['port'], $pack);
 		} finally {
 			$event = Snowflake::app()->event;
 			$event->trigger(Event::SERVER_WORKER_STOP);
diff --git a/HttpServer/Events/Utility/DataResolve.php b/HttpServer/Events/Utility/DataResolve.php
index 6d1f1d7c..12237f37 100644
--- a/HttpServer/Events/Utility/DataResolve.php
+++ b/HttpServer/Events/Utility/DataResolve.php
@@ -26,9 +26,14 @@ class DataResolve
 	public static function pack($unpack, $data)
 	{
 		if (empty($unpack)) {
-			return JSON::encode($data);
+			$params = JSON::encode($data);
+		} else {
+			$params = self::callbackResolve($unpack, null, null, $data);
 		}
-		return self::callbackResolve($unpack, null, null, $data);
+		if ($params === null) {
+			return 'Format error.';
+		}
+		return $params;
 	}
 
 
@@ -44,9 +49,14 @@ class DataResolve
 	public static function unpack($unpack, $address, $port, $data)
 	{
 		if (empty($unpack)) {
-			return JSON::decode($data);
+			$params = JSON::decode($data);
+		} else {
+			$params = self::callbackResolve($unpack, $address, $port, $data);
 		}
-		return self::callbackResolve($unpack, $address, $port, $data);
+		if ($params === null) {
+			return 'Format error.';
+		}
+		return $params;
 	}