无法使用Node JS和Firestore / Firebase发送通知

Question

我创建了一个小功能，可以向用户发送通知。令牌ID将从数据库中获取，并且通知应发送到该设备。即使该功能在控制台中绝对可以运行。即使发送通知，我也收到了设置的响应，但这对设备没有影响。 我正在尝试将通知发送到主要是Ipad的Iphone设备

代码在这里

exports.SendNotification = functions.firestore.document("UserData/{user_id}").onWrite((change, context) => {

    const user_id = context.params.user_id;



    console.log('We have a notification to send to :', user_id);




    return admin.firestore().collection("UserData").doc(user_id).get()

       .then(snapshot2 =>
         {

           const Message =snapshot2.data().msg;
           const token_id =snapshot2.data().token_id;

          console.log(" Message: ", Message);
          console.log(" Token_id: ",token_id);



        const payload =
        {
            notification:
            {
                title: "Notification",
                body: "Hi this is to notify you",
                icon: "default"
            }
        };

        return admin.messaging().sendToDevice(token_id, payload)
                    .then(response =>
                    {
                      return  console.log('Second notification is also send successfully');
                    });
    });
});