As your binding code only retrieves data from database and bind it to grid view, I suggest to bind it as mentioned below :
Design Page:
<asp:GridView ID="gridviewformindexteknis" runat="server"
AutoGenerateColumns="false" BackColor="White"
BorderColor="#E7E7FF" BorderStyle="None" BorderWidth="1px" CellPadding="3"
AllowPaging="false" OnPageIndexChanging="PageIndexChanging"
Style="overflow: auto" Width="100%">
<FooterStyle BackColor="#B5C7DE" ForeColor="#4A3C8C" />
<RowStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" />
<PagerStyle BackColor="#E7E7FF" ForeColor="#4A3C8C" HorizontalAlign="Right" />
<SelectedRowStyle BackColor="#738A9C" Font-Bold="True" ForeColor="#F7F7F7" />
<HeaderStyle BackColor="#4A3C8C" Font-Bold="True" ForeColor="#F7F7F7" />
<AlternatingRowStyle BackColor="#F7F7F7" />
<Columns>
<asp:BoundField DataField="deskripsi" HeaderText="Deskripsi" />
<asp:BoundField DataField="deskripsi" HeaderText="Deskripsi" />
<asp:BoundField DataField="customername" HeaderText="Customer" />
<asp:BoundField DataField="remarks" HeaderText="Remarks" />
<asp:HyperLinkField HeaderText="Nomer Billing" Target="_blank" DataNavigateUrlFields="BillingNo" DataTextField="BillingNo" DataNavigateUrlFormatString="~/detailBillingTek.aspx?BillingNo={0}" />
</Columns>
</asp:GridView>
Code Behind :
SqlConnection tarikdatakondisi1 = new SqlConnection(StartKoneksiDatatable());
tarikdatakondisi1.Open();
SqlDataAdapter sda1 = new SqlDataAdapter("select BillingNo, deskripsi, customername, remarks from mastertablebilling where tablestatusId = 1 and billingstatusId = 1", tarikdatakondisi1);
DataTable dt1 = new DataTable();
sda1.Fill(dt1);
gridviewformindexteknis.DataSource = dt1;
gridviewformindexteknis.DataBind();
tarikdatakondisi1.Close();