diff --git a/NanaGet/NanaGet.JsonRpc2.cpp b/NanaGet/NanaGet.JsonRpc2.cpp
index 0dcc023..16c0492 100644
--- a/NanaGet/NanaGet.JsonRpc2.cpp
+++ b/NanaGet/NanaGet.JsonRpc2.cpp
@@ -19,10 +19,7 @@ std::string NanaGet::JsonRpc2::FromRequestMessage(
         ResultJson["jsonrpc"] = "2.0";
         ResultJson["method"] = Value.Method;
         ResultJson["params"] = nlohmann::json::parse(Value.Parameters);
-        if (!Value.IsNotification)
-        {
-            ResultJson["id"] = Value.Identifier;
-        }
+        ResultJson["id"] = Value.Identifier;
         return ResultJson.dump(2);
     }
     catch (...)
diff --git a/NanaGet/NanaGet.JsonRpc2.h b/NanaGet/NanaGet.JsonRpc2.h
index 8c2c47b..bbcf933 100644
--- a/NanaGet/NanaGet.JsonRpc2.h
+++ b/NanaGet/NanaGet.JsonRpc2.h
@@ -29,10 +29,6 @@ namespace NanaGet::JsonRpc2
      */
     struct RequestMessage
     {
-        /**
-         * @brief true if this request is a notification. Otherwise false.
-         */
-        bool IsNotification = false;
         /**
          * @brief A string containing the name of the method to be invoked.
          *        method names that begin with the word rpc followed by a period
@@ -40,12 +36,14 @@ namespace NanaGet::JsonRpc2
          *        methods and extensions and MUST NOT be used for anything else.
          */
         std::string Method;
+
         /**
          * @brief A structured JSON value that holds the parameter values to be
          *        used during the invocation of the method. This member MAY be
          *        omitted.
          */
         std::string Parameters;
+
         /**
          * @brief An identifier established by the client. If it is not included
          *        it is assumed to be a notification. The value SHOULD normally
diff --git a/NanaGet/NanaGetCore.cpp b/NanaGet/NanaGetCore.cpp
index e13e52a..a5d5989 100644
--- a/NanaGet/NanaGetCore.cpp
+++ b/NanaGet/NanaGetCore.cpp
@@ -486,7 +486,6 @@ std::string NanaGet::Aria2Instance::SimpleJsonRpcCall(
     std::string const& Parameters)
 {
     NanaGet::JsonRpc2::RequestMessage Request;
-    Request.IsNotification = false;
     Request.Method = MethodName;
     Request.Parameters = Parameters;
     Request.Identifier = winrt::to_string(NanaGet::CreateGuidString());