SqlDependency OnChange event not working with Join query in ASP.Net

hi ,

i am working with sql dependence signalr in webforms its all working fine but when i am using joins in my select query then dependency_OnChange event not working

working with simple select statment

            //Qry = "SELECT [MessageID], [Message], [EmptyMessage], [Date] FROM [dbo].[Messages1] WHERE ID='1'";

            Qry = "SELECT  CL.[ID], CL.[NAME] FROM [dbo].[tblclientClientUser] AS CL     INNER join  tblclients c on c.ID =cl.Comp_ID  ";
            //      Qry = "SELECT   ID, Name, Tag FROM dbo.tblclients";
            Qry = "SELECT [MessageID], [Message], [EmptyMessage]+U.[UNAME] AS EmptyMessage, [Date] FROM [dbo].[Messages1] INNER JOIN TBLUSERS  U ON U.UID = Messages1.UID    WHERE ID='1'";
            using (var command = new SqlCommand(Qry, connection))
            {
                command.Notification = null;

                var dependency = new SqlDependency(command);
                dependency.OnChange += new OnChangeEventHandler(dependency_OnChange);

                if (connection.State == ConnectionState.Closed)
                    connection.Open();


                SqlDataAdapter customerDA = new SqlDataAdapter();
                customerDA.SelectCommand = command;

                customerDA.Fill(Ds);
            }
    private static void dependency_OnChange(object sender, SqlNotificationEventArgs e)
    {
        if (e.Type == SqlNotificationType.Change)
        {
            // MessagesHub.SendMessages();
            SqlDependency dependency = (SqlDependency)sender;
            dependency.OnChange -= new OnChangeEventHandler(dependency_OnChange);
            MyHub.Show();
        }
    }