Yardım VB DataGridView3 temizleme sorunu

    Sub add_order()

        Dim connection As String = ConfigurationManager.ConnectionStrings("mysql").ConnectionString
   

        Dim ds As New DataSet
        Dim sa As New MySqlDataAdapter("SELECT * FROM  order where aktarma =0 ", connection)
        sa.Fill(ds)
        DataGridView2.DataSource = ds.Tables(0)
        DataGridView2.Refresh()
        DataGridView3.Refresh()

        For i = 0 To ds.Tables(0).Rows.Count - 1
            Dim order = uapp.NewDataObject(UnityObjects.DataObjectType.doSalesOrderSlip)
            order.New()

            Dim order_id = Replace(ds.Tables(0).Rows(i).Item("order_id"), " ", "")
            Dim CUSTEM = Replace(ds.Tables(0).Rows(i).Item("CUSTEM"), " ", "")
            Dim currency_code = Replace(ds.Tables(0).Rows(i).Item("currency_code"), " ", "")
            Dim date_added = (ds.Tables(0).Rows(i).Item("date_added"))
            Dim gelen = order_id

            Dim dt As DateTime = Convert.ToDateTime(date_added)
            Dim format As String = "dd.MM.yyyy"
            Dim TARIH As String = dt.ToString(format)




            order.DataFields.FieldByName("NUMBER").Value = "~"
            order.DataFields.FieldByName("DATE").Value = TARIH
            order.DataFields.FieldByName("DOC_NUMBER").Value = "WEB"
            order.DataFields.FieldByName("AUXIL_CODE").Value = "WEB"
            order.DataFields.FieldByName("ARP_CODE").Value = CUSTEM
            order.DataFields.FieldByName("ORDER_STATUS").Value = 1
            order.DataFields.FieldByName("CURRSEL_TOTAL").Value = 2
            order.DataFields.FieldByName("CURRSEL_DETAILS").Value = 2
            order.DataFields.FieldByName("RC_RATE").Value = 1
            order.DataFields.FieldByName("DATA_SITEID").Value = 1


            Dim connection2 As String = ConfigurationManager.ConnectionStrings("mysql").ConnectionString
            Dim gs As New DataSet
            Dim ea As New MySqlDataAdapter("SELECT * FROM product  where order_id = '" & gelen & "' ", connection2)
        
            ea.Fill(gs)
            DataGridView3.DataSource = gs.Tables(0).DefaultView
            DataGridView3.Refresh()



            Dim transactions_lines = order.DataFields.FieldByName("TRANSACTIONS").Lines

            For ia = 0 To gs.Tables(0).Rows.Count - 1
                Dim order_id2 = Replace(gs.Tables(0).Rows(ia).Item("order_id"), " ", "")
                If (order_id = order_id2) Then

                    Dim STOCKREF = Replace(gs.Tables(0).Rows(ia).Item("model"), " ", "")
                    Dim PRICE = gs.Tables(0).Rows(ia).Item("price")
                    Dim AMOUNT = gs.Tables(0).Rows(ia).Item("quantity")


                    transactions_lines.AppendLine()
                    transactions_lines((0)).FieldByName("TYPE").Value = 0
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("MASTER_CODE").Value = STOCKREF
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("QUANTITY").Value = AMOUNT
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("PRICE").Value = PRICE
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("VAT_RATE").Value = ""
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("UNIT_CODE").Value = "ADET"
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("UNIT_CONV1").Value = 1
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("UNIT_CONV2").Value = 1
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("DUE_DATE").Value = TARIH
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("MULTI_ADD_TAX").Value = 0
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("EDT_CURR").Value = 1
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("ORG_DUE_DATE").Value = TARIH
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("ORG_QUANTITY").Value = 1
                    transactions_lines((transactions_lines.Count - 1)).FieldByName("ORG_PRICE").Value = PRICE


                    If (currency_code = "USD") Then
                        order.DataFields.FieldByName("CURR_TRANSACTIN").Value = 1
                    Else
                        order.DataFields.FieldByName("CURR_TRANSACTIN").Value = 20
                    End If



                End If
            Next

            If (order.Post() = True) Then
                Dim connection3 As MySqlConnection
                connection3 = New MySqlConnection
                connection3.ConnectionString = ConfigurationManager.ConnectionStrings("mysql").ConnectionString
                connection3.Open()
                Dim SQLCOMMANDSTRING As String = "UPDATE  order SET aktarma='1'  WHERE order_id='" & order_id & "' "
                Dim SqlCommand As New MySqlCommand(SQLCOMMANDSTRING, connection3)
                Dim Count As Integer

                Count = SqlCommand.ExecuteNonQuery

                connection3.Close()



                ' MsgBox("POST OK !")

            End If


            If order.ErrorCode <> 0 Then
                MsgBox("DB Error:(" + CStr(order.ErrorCode) + ") - " + order.ErrorDesc)
            Else
                If order.ValidateErrors.Count > 0 Then
                    For ai = 0 To order.ValidateErrors.Count - 1
                        MsgBox("XML Error :(" + CStr(order.ValidateErrors.Item(i).ID) + ")-" + order.ValidateErrors.Item(ai).Error)
                    Next ai
                End If



            End If




        Next



        conn.Close()
    End Sub


    Private Sub Label1_Click(sender As Object, e As EventArgs) Handles Label1.Click

    End Sub

    Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load

    End Sub


    ' Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
    '    connect()
    '   add_order()
    'End Sub

    Private Sub Button4_Click(sender As Object, e As EventArgs) Handles Button4.Click
        Dim timer = New Timer
        timer.Interval = 60 * 1000
        AddHandler timer.Tick, AddressOf timer_Tick
        timer.Start()

        connect()
        add_order()


    End Sub