when i retreiving 0 in dropdownlist then error is coming

Databinding methods such as Eval(), XPath(), and Bind() can only be used in the context of a databound control.

    </style><asp:GridView ID="GridView1" runat="server" AutoGenerateSelectButton="false"  AutoGenerateColumns="false" BackColor="White" BorderColor="#E7E7FF" BorderStyle="None" BorderWidth="1px" CellPadding="3" GridLines="Horizontal" Height="229px" style="margin-bottom: 53px" Width="1055px" OnRowDataBound="GridView1_RowDataBound" OnRowUpdating="GridView1_RowUpdating" OnSelectedIndexChanged="GridView1_SelectedIndexChanged">
    <AlternatingRowStyle BackColor="#F7F7F7" />
    <FooterStyle BackColor="#B5C7DE" ForeColor="#4A3C8C" />
    <HeaderStyle BackColor="#4A3C8C" Font-Bold="True" ForeColor="#F7F7F7" />
    <PagerStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" HorizontalAlign="Right" />
    <RowStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" />
    <SelectedRowStyle BackColor="#738A9C" Font-Bold="True" ForeColor="#F7F7F7" />
    <SortedAscendingCellStyle BackColor="#F4F4FD" />
    <SortedAscendingHeaderStyle BackColor="#5A4C9D" />
    <SortedDescendingCellStyle BackColor="#D8D8F0" />
    <SortedDescendingHeaderStyle BackColor="#3E3277" />
        <Columns>
                 <asp:BoundField DataField="ID" HeaderText="ID" Visible="True" />
                <asp:TemplateField HeaderText="Date">
                                    <ItemTemplate>
                                        <asp:Label ID="Date" runat="server" Text='<%#Bind("Date")%>'></asp:Label>
                                    </ItemTemplate>
            </asp:TemplateField>
              <asp:TemplateField HeaderText="Head">
                                    <ItemTemplate>
                                        <asp:Label ID="Head" runat="server" Text='<%#Bind("Head")%>'></asp:Label>
                                    </ItemTemplate>
            </asp:TemplateField>
                 <asp:TemplateField HeaderText="Cheque_No" >
                                    <ItemTemplate>
                                        <asp:Label ID="Cheque_No" runat="server"  Text='<%#Bind("Cheque_No")%>'></asp:Label>
                                    </ItemTemplate>
            </asp:TemplateField>

               <asp:TemplateField HeaderText="Cheque_Date">
                                    <ItemTemplate>
                                        <asp:Label ID="Cheque_Date" runat="server" Text='<%#Bind("Cheque_Date")%>'></asp:Label>
                                    </ItemTemplate>
            </asp:TemplateField>
                       <asp:TemplateField HeaderText="Cheque_Bank">
                                    <ItemTemplate>
                                        <asp:Label ID="Cheque_Bank" runat="server" Text='<%#Bind("Cheque_Bank")%>'></asp:Label>
                                    </ItemTemplate>
            </asp:TemplateField>
                <asp:TemplateField HeaderText="Cheque_Branch">
                                    <ItemTemplate>
                                        <asp:Label ID="Cheque_Branch" runat="server" Text='<%#Bind("Cheque_Branch")%>'></asp:Label>
                                    </ItemTemplate>
            </asp:TemplateField>
                  <asp:TemplateField HeaderText="Amount" ItemStyle-HorizontalAlign="Right">
                                    <ItemTemplate>
                                        <asp:Label ID="Amount" CssClass="right_align"  ItemStyle-HorizontalAlign="Right" runat="server" Text='<%#Bind("Amount")%>'></asp:Label>
                                    </ItemTemplate>
            </asp:TemplateField>
                 <asp:CommandField ButtonType="link"  ItemStyle-HorizontalAlign="Center"   ControlStyle-ForeColor="Blue " ControlStyle-Height="20px" ShowSelectButton="true" SelectText="Transfer" >
            <ControlStyle ForeColor="Blue" Height="20px" />
            </asp:CommandField>
                  <asp:TemplateField HeaderText="Bank" ItemStyle-HorizontalAlign="Right">

                                    <ItemTemplate>
                                     <asp:Label ID="lbbank" runat="server" />
                                <asp:DropDownList ID="ddlbank" runat="server" Text='<%#Bind("ddlbank")%>'   Height="85px" Width="150px">
                               <asp:ListItem Text="Select" value="0" />
                                    </asp:DropDownList>
                                        </ItemTemplate>
            </asp:TemplateField>
        </Columns>
    </asp:GridView>

ALTER Proc [dbo].[Sp_Ret_Transection_CHeq]
as begin

 SELECT T.Trans_ID as ID,COnvert(varchar,T.Trans_Date,101) as Date,COA.Level_Four_Name as Head,T.Cheque_No ,
 Convert(varchar,T.Cheque_Date,101) as Cheque_Date,T.Cheque_Bank,T.Cheque_Branch,'0' as ddlbank
 --  REPLACE(CONVERT(varchar(20),cast(T.Trans_Amount as money))) as Amount 
 
,(CONVERT(varchar(50), CAST(t.Trans_Amount AS money),1)) as Amount,T.Cheque_Status 
 FROM tbl_transection T
 inner join tbl_COA COA on COA.Level_Four_ID=T.Level_Four_ID_C
 where T.Trans_Type_ID=2 and T.Cheque_Status is null
 end

        protected void GridView1_RowDataBound(object sender, GridViewRowEventArgs e)
        {
            if (e.Row.RowType == DataControlRowType.DataRow)
            {

                DropDownList ddlbank = (DropDownList)e.Row.FindControl("ddlbank");
                SqlCommand cmd = new SqlCommand("select Level_Four_ID,Level_Four_Name from tbl_COA where Level_Three_ID=3102 ", con);
                SqlDataAdapter sda = new SqlDataAdapter(cmd);

                DataTable dt = new DataTable();

                sda.Fill(dt);
                ddlbank.DataSource = dt;
                ddlbank.DataTextField = "Level_Four_Name";
                ddlbank.DataValueField = "Level_Four_ID";

                ddlbank.DataBind();

                ddlbank.Items.Insert(0, new ListItem("--Select Bank--", "0"));
            }
        }