Oracle SQL Query Working in SQL Developer but not in ASP.NET

SELECT a.ship_date ,a.judge_flag from ship_pallet_info  a inner join ship_request_info
b on a.ship_request_no = b.ship_request_no
where a.ship_date between :date1 and :date2 and a.judge_flag= :judgement;



and same query in ASP.NET like this but does not return any value:

<pre lang="vb">code.OCon.Close()
          code.OCon.Open()
          Dim cmd As New OracleCommand(&quot;SELECT * from ship_pallet_info  a inner join ship_request_info  b on a.ship_request_no = b.ship_request_no where a.ship_date between :date1 and :date2 and a.judge_flag = :judge&quot;, code.OCon)
          cmd.Parameters.Add(New OracleParameter(&quot;date1&quot;, txtPeriod_1.Text))
          cmd.Parameters.Add(New OracleParameter(&quot;date2&quot;, txtPeriod_1.Text))
          cmd.Parameters.Add(New OracleParameter(&quot;judge&quot;, txtPeriod_1.Text))
          Dim dt As New DataTable
          Dim da As New OracleDataAdapter(cmd)
          da.Fill(dt)
          gvShippingStatus.DataSource = dt
          gvShippingStatus.DataBind()</pre>