กดบันทึกข้อมูลแล้ว ข้อมูลไม่เข้า...... ตามนี้เลยครับ ข้อมูลของ Listbox ไม่เข้าครับ

Private Sub btnSave_Click(sender As Object, e As EventArgs) Handles btnSave.Click
        Dim Conn As New OleDbConnection(strConnection)
        Dim Comm As New OleDb.OleDbCommand()

        Conn.Open()
        Dim strSQL As String
        Dim strSQL2 As String

        strSQL = "insert into [GROUP_USERS] ([GROUP_USER],[USER_NAME],[Create_Date]) values ('" & TextBox1.Text & "','" & ListBox1.Text & "', getdate()) "
        strSQL2 = "insert into [PERMISSION_REPORTS] ([GROUP_USER],[USER_NAME],[Create_Date]) values ('" & TextBox1.Text & "','" & ListBox1.Text & "', getdate())"
        Dim i As Integer

        Comm.Connection = Conn
        Comm.CommandType = CommandType.Text
        Comm.CommandText = strSQL
        Comm.ExecuteNonQuery()
        Comm.CommandText = strSQL2
        Comm.ExecuteNonQuery()
        For i = 0 To ListBox1.Items.Count - 1
            Comm.Parameters.AddWithValue("USER_NAME", ListBox1.Items.Item(i))

        Next
        Comm.ExecuteNonQuery()
        Conn.Dispose()
        Comm.Dispose()
        'MessageBox.Show(strSQL)
        Me.Close()
        User_Group_List.Show()
    End Sub