This is my listview when i insert somthing to form one time the listview of the form show it 3 tiem, waht could be the error,

Sub loadlistview()
        Me.ListView1.View = View.Details
        Me.ListView1.GridLines = True
        Dim conn As New SqlConnection("Data Source=localhost;Initial Catalog=TrackingUnitsInventorySystem;Integrated Security=True")
        conn.Open()
        ListView1.Items.Clear()
        ListView1.Columns.Clear()
        Dim cmd As New SqlCommand("SELECT * from vSale", conn)
        cmd.CommandType = CommandType.Text
        Dim reader As SqlDataReader = cmd.ExecuteReader()
        Me.ListView1.Columns.Add("IMEI No")
        Me.ListView1.Columns(0).Width = 150
        Me.ListView1.Columns.Add("Invoice No")
        Me.ListView1.Columns(1).Width = 100
        Me.ListView1.Columns.Add("Alternate Code")
        Me.ListView1.Columns(2).Width = 100
        Me.ListView1.Columns.Add("SaleOrder")
        Me.ListView1.Columns(3).Width = 150
        Me.ListView1.Columns.Add("Status")
        Me.ListView1.Columns(4).Width = 150
        Me.ListView1.Columns.Add("Accessroy Type/Category")
        Me.ListView1.Columns(5).Width = 150
        Me.ListView1.Columns.Add("Origin")
        Me.ListView1.Columns(6).Width = 100
        Me.ListView1.Columns.Add("Warranty")
        Me.ListView1.Columns(7).Width = 150
        Me.ListView1.Columns.Add("Company")
        Me.ListView1.Columns(8).Width = 100
        Me.ListView1.Columns.Add("Sale Date")
        Me.ListView1.Columns(9).Width = 100
        Me.ListView1.Columns.Add("Party Name")
        Me.ListView1.Columns(10).Width = 150
        Me.ListView1.Columns.Add("Received By")
        Me.ListView1.Columns(11).Width = 150
        Me.ListView1.Columns.Add("Receiving Medium")
        Me.ListView1.Columns(12).Width = 100
        Me.ListView1.Columns.Add("Unit Quantity")
        Me.ListView1.Columns(13).Width = 150
        Me.ListView1.Columns.Add("Total to Party")
        Me.ListView1.Columns(14).Width = 100
        Me.ListView1.Columns.Add("Total Sold")
        Me.ListView1.Columns(15).Width = 100
        Me.ListView1.Columns.Add("Remarks")
        Me.ListView1.Columns(16).Width = 100
        While reader.Read()
            Dim NewItem As New ListViewItem
            With NewItem
                .Text = reader("IMEINo").ToString
                With .SubItems
                    .Add(reader("InvoiceNo").ToString)
                    .Add(reader("AlternateCode").ToString)
                    .Add(reader("SaleOrder").ToString)
                    .Add(reader("Status").ToString)
                    .Add(reader("Category").ToString)
                    .Add(reader("Origin").ToString)
                    .Add(reader("Warranty").ToString)
                    .Add(reader("Company").ToString)
                    .Add(reader("SaleDate").ToString)
                    .Add(reader("PartyName").ToString)
                    .Add(reader("Recviedby").ToString)
                    .Add(reader("RecviedThrough").ToString)
                    .Add(reader("UnitQty").ToString)
                    .Add(reader("SoldToParty").ToString)
                    .Add(reader("TotalSold").ToString)
                    .Add(reader("Remarks").ToString)
                    ListView1.Items.Add(NewItem)
                End With
            End With

        End While
        reader.Close()
        conn.Close()
    End Sub