Checkbox asp.net c# Grid

I currently have a DataGrid that "SELECT * FROM table WHERE Hentet = 'nej';" under that grid i have a exact copy of it, but "WHERE Hentet = 'Ja';" as you will see in the code. both grid's work fine and get the data they are supposed to get, however there is a checkbox on each row of "Grid 1", so you can Select Whatever Rows, Press the button and i want the value 'Nej'; to change to 'Ja'; on that button Click, so the rows with a checked checkbox will be moved to Grid2, now that their value is = 'Ja'. Grid2 does not have a checkbox column, so its only from grid1 to grid2, and not both ways.

Grid 1

    <asp:DataGrid ID="GridView1" runat="server" DataSourceID="SqlDataSource1" AutoGenerateColumns="false">
           <Columns>
           <asp:TemplateColumn>
               <ItemTemplate>
               <asp:CheckBox ID="CheckBox1" runat="server"></asp:CheckBox>
                   </ItemTemplate>
           </asp:TemplateColumn>

           <asp:BoundColumn DataField="dato" HeaderText="Dato">
            </asp:BoundColumn>
            <asp:BoundColumn DataField="Antal" HeaderText="Antal">
            </asp:BoundColumn>
           <asp:Boundcolumn HeaderText="Navn" Datafield="VareNAvn">
            </asp:Boundcolumn>
       <asp:BoundColumn DataField="KøbtAfBrugerID" HeaderText="Købt af ID">
            </asp:BoundColumn>
            <asp:Boundcolumn HeaderText="Hented" DataField="Afhented">
                </asp:Boundcolumn>
       </Columns>
    </asp:DataGrid>
  <asp:Button ID="Button_Hented" CssClass="btfarve" runat="server" Text="Afhentet" OnClick="Button_Hented_Click" />
    <asp:SqlDataSource ID="SqlDataSource1" runat="server" 
    ConnectionString="<%$ ConnectionStrings:DatabaseConnectionString1 %>" 
    SelectCommand="SELECT * FROM [Transactioner] WHERE afhented ='Nej';">
    </asp:SqlDataSource>

Grid2

<asp:DataGrid ID="GridView2" runat="server" DataSourceID="SqlDataSource2" AutoGenerateColumns="false">

           <Columns>
               <asp:BoundColumn DataField="dato" HeaderText="Dato">
                </asp:BoundColumn>
                <asp:BoundColumn DataField="Antal" HeaderText="Antal">
                </asp:BoundColumn>
               <asp:Boundcolumn HeaderText="Navn" Datafield="VareNAvn">
                </asp:Boundcolumn>
            <asp:BoundColumn DataField="KøbtAfBrugerID" HeaderText="Købt af ID">
                </asp:BoundColumn>
                <asp:Boundcolumn HeaderText="Hented" DataField="Afhented">
                    </asp:Boundcolumn>
           </Columns>
        </asp:DataGrid>
        <asp:SqlDataSource ID="SqlDataSource2" runat="server" 
        ConnectionString="<%$ ConnectionStrings:DatabaseConnectionString1 %>" 
        SelectCommand="SELECT * FROM [Transactioner] WHERE afhented ='Ja';">
        </asp:SqlDataSource>

Code Behind

protected void Button_Hented_Click(object sender, EventArgs e)
     {
         string Hejsa;

         SqlConnection conn = new SqlConnection();
         conn.ConnectionString = ConfigurationManager.ConnectionStrings["DatabaseConnectionString1"].ToString();

         SqlCommand cmd = new SqlCommand();
         cmd.Connection = conn;
         cmd.CommandText = "SELECT * FROM Transactioner";



         conn.Open();
         SqlDataReader reader = cmd.ExecuteReader();

         if (reader.Read())
         {

             Hejsa = reader["Id"].ToString();



             foreach (DataGridItem item in GridView1.Items)
             {
                 CheckBox Cb = item.Cells[0].Controls[1] as CheckBox;


                 if (Cb.Checked)
                 {

                     SqlConnection conn2 = new SqlConnection();
                     conn2.ConnectionString =
                         ConfigurationManager.ConnectionStrings["DatabaseConnectionString1"].ToString();
                     SqlCommand cmd2 = new SqlCommand();
                     cmd2.Connection = conn2;

                     cmd2.CommandText = "UPDATE Transactioner"
                         + " SET Afhented = @Afhented"
                         + " where Id = @Id";


                     cmd2.Parameters.Add("@Afhented", SqlDbType.NVarChar).Value = "Ja";
                     cmd2.Parameters.Add("@Id", SqlDbType.Int).Value = Hejsa;


                     conn2.Open();
                     cmd2.ExecuteNonQuery();
                     conn2.Close();

                 }

             }
             Response.Redirect(Request.RawUrl);

         }
         conn.Close();

        }

So this is all the code, I get NO error messages atall and i really cant see what is wrong again, All i really want the code to do is on button click, if checkbox is checked, change the value 'Nej' to 'Ja'. Sorry if my question was hard to understand. Tekar