diff --git a/app/src/main/java/com/example/tampopo_client/viewmodels/ChatViewModel.java b/app/src/main/java/com/example/tampopo_client/viewmodels/ChatViewModel.java
index 3f0ca2c..0c5a721 100644
--- a/app/src/main/java/com/example/tampopo_client/viewmodels/ChatViewModel.java
+++ b/app/src/main/java/com/example/tampopo_client/viewmodels/ChatViewModel.java
@@ -1,5 +1,7 @@
 package com.example.tampopo_client.viewmodels;
 
+import android.os.Handler;
+import android.os.Looper;
 import android.util.Log;
 
 import java.util.ArrayList;
@@ -8,17 +10,35 @@
 public class ChatViewModel extends RealTimeViewModel {
     private final List<NotificationListener> notificationListeners = new ArrayList<>();
 
-    private static final double NOTIFICATION_RECEIVE_PROBABILITY = 0.01;
+    //private static final double NOTIFICATION_RECEIVE_PROBABILITY = 0.5;
 
+    //natty
+    private boolean notificationSent = false; // 一度だけ送信するためのフラグ
+
+
+//    @Override
+//    public Runnable onUpdate() {
+//        return () -> {
+//            // 1% の確率で onNotificationReceived() が呼び出される
+//            double borderValue = Math.floor(Math.random() * 100);
+//            double currentValue = NOTIFICATION_RECEIVE_PROBABILITY * 100;
+//            if (currentValue >= borderValue) {
+//                Log.d("ChatViewModel", "Received test notification.");
+//                notificationListeners.forEach(listener -> listener.onNotificationReceived());
+//            }
+//        };
+//    }
+    //natty
     @Override
     public Runnable onUpdate() {
         return () -> {
-            // 1% の確率で onNotificationReceived() が呼び出される
-            double borderValue = Math.floor(Math.random() * 100);
-            double currentValue = NOTIFICATION_RECEIVE_PROBABILITY * 100;
-            if (currentValue >= borderValue) {
-                Log.d("ChatViewModel", "Received test notification.");
-                notificationListeners.forEach(listener -> listener.onNotificationReceived());
+            if (!notificationSent) {
+                // 10秒後に一回だけ通知を送る
+                notificationSent = true; // もう送らない
+                new Handler(Looper.getMainLooper()).postDelayed(() -> {
+                    Log.d("ChatViewModel", "Received test notification (after 10s).");
+                    notificationListeners.forEach(NotificationListener::onNotificationReceived);
+                }, 10_000); // 10秒(10000ms)
             }
         };
     }