مشكلة في عمل update في احدى شاشات البرنامج

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
Dim D, DD, DDD As Double
If DR.IsClosed = False Then
DR.Close()
End If
CMD.CommandText = "Select * from sid where SaleID = " & TextBox1.Text & ""
DR = CMD.ExecuteReader
DR.Read()
If DR.HasRows = False Then
D = 1
Else
CMD.CommandText = "Select count(SaleID) from sid where SaleID = " & TextBox1.Text & ""
D = CMD.ExecuteScalar + 1
End If
DR.Close()
CMD.CommandText = "select * from items_m where it_1 = '" & ComboBox4.Text & "' and it_7 = '" & ComboBox3.Text & "' and it_4 = '" & ComboBox2.Text & "'"
DR = CMD.ExecuteReader
DR.Read()
DDD = DR("id_item")
DD = DR("it_9")
If DD < Val(TextBox3.Text) Then
MsgBox("عفوا الكمية المطلوبة من هذا الصنف غير متوفرة في المخزن")
Exit Sub
End If
Dim X As String = "بيع"
DR.Close()
Dim F1, F2, F3 As String
F1 = "'" & DD - Val(TextBox3.Text) & "',"
F2 = "'" & X & "',"
F3 = "'" & Val(TextBox2.Text) & "'"
CMD.CommandText = "update items_m set it_9 = " & F1 & "it_13 = " & F2 & "it_14 = " & F3 & ""
CMD.ExecuteNonQuery()
Dim D1, D2, D3, D4, D5, D6, D7, D8, D9, D10, D11 As String
D1 = "'" & TextBox1.Text & "',"
D2 = "'" & A & "',"
D3 = "'" & D & "'"
D4 = "'" & DDD & "',"
D5 = "'" & ComboBox2.Text & "',"
D6 = "'" & ComboBox4.Text & "',"
D7 = "'" & DateTimePicker1.Value & "',"
D8 = "'" & ComboBox1.Text & "'"
D9 = "'" & TextBox2.Text & "',"
D10 = "'" & TextBox3.Text & "',"
D11 = "'" & TextBox4.Text & "'"
CMD.CommandText = "insert into sid (SaleID,StoreID,Sort,ItemID,ItemName,ItemGroup,A_Date,CustName,Cost,Quan,Amount) Values (" & D1 & D2 & D3 & D4 & D5 & D6 & D7 & D8 & D9 & D10 & D11 & ")"
MsgBox(CMD.ExecuteNonQuery & " Record Saved")
CMD.CommandText = "select * from sid where SaleID = '" & TextBox1.Text & "'"
DR = CMD.ExecuteReader()
DR.Read()
TextBox5.Text = Val(TextBox5.Text) + DR("Quan")
DR.Close()
Dim TBL As New DataTable
CMD.CommandText = "select * from sid where SaleID = " & TextBox1.Text & ""
DR = CMD.ExecuteReader()
DataGridView1.DataSource = Nothing
TBL.Load(DR)
DataGridView1.DataSource = TBL
DataGridView1.Columns(0).Visible = False
DataGridView1.Columns(1).HeaderCell.Value = "رقم الفاتورة"
DataGridView1.Columns(2).HeaderCell.Value = "رقم المخزن"
DataGridView1.Columns(3).HeaderCell.Value = "رقم الصنف في الفاتورة"
DataGridView1.Columns(4).HeaderCell.Value = "رقم الصنف"
DataGridView1.Columns(5).HeaderCell.Value = "اسم الصنف"
DataGridView1.Columns(6).HeaderCell.Value = "المجموعة"
DataGridView1.Columns(7).HeaderCell.Value = "تاريخ الفاتورة"
DataGridView1.Columns(8).HeaderCell.Value = "اسم المورد"
DataGridView1.Columns(9).HeaderCell.Value = "السعر"
DataGridView1.Columns(10).HeaderCell.Value = "الكمية"
DataGridView1.Columns(11).HeaderCell.Value = "القيمة"
DateTimePicker1.Enabled = False
ComboBox1.Enabled = False
ComboBox3.Enabled = False
ComboBox2.Text = ""
ComboBox4.Text = ""
TextBox2.Text = ""
TextBox3.Text = ""
TextBox4.Text = ""
End Sub