How do I reuse the same device instance to scan multiple documents from the selected device using WIA (Windows Image Acquisition)?

Question

I have a vb.net project that allow the user to click on a button to perform scan. On clicking of the button, it will display a commonDialog box that let user select a connected scanner device, thereby I will programmatically set the properties for the scan (ie: A4 size scan, greyscale etc).

Using a while loop, I allow the user to scan more than a single document. My code goes as below:

Private Sub ScanAndSaveMultipleDocuments()

    Dim pdfFilePath As String = "examplePath"
    Dim pdfDocument As New iText.Kernel.Pdf.PdfDocument(New PdfWriter(pdfFilePath))
    Dim document As Document
    Dim isMorePage As Boolean = True
    Try
        If Not Directory.Exists(tempPath) Then
            Directory.CreateDirectory(tempPath)
        End If

        Dim documentIndex As Integer = 0
        While isMorePage = True
            SetScannerDevice()

            Dim scannedImage As ImageFile = ScanImage()

            If scannedImage IsNot Nothing Then
                Dim scannedImageBytes As Byte() = RevieweScannedImage(scannedImage)

                If scannedImageBytes IsNot Nothing Then
                    Dim pdfImage As New Image(iText.IO.Image.ImageDataFactory.Create(scannedImageBytes))
                    document = New Document(pdfDocument, New iText.Kernel.Geom.PageSize(pdfImage.GetImageWidth(), pdfImage.GetImageHeight()))
                    pdfImage.SetFixedPosition(documentIndex + 1, 0, 0)
                    document.Add(pdfImage)

                    documentIndex += 1
                End If
                If MsgBoxResult.Yes <> MsgBox("Are there more document to scan?", MsgBoxStyle.YesNo) Then isMorePage = False
            Else
                pdfDocument.Close()
                Exit While
            End If
        End While

        If pdfDocument IsNot Nothing AndAlso Not pdfDocument.IsClosed Then pdfDocument.Close()
        If documentIndex = 0 Then Return

        Dim doc As REF_InvoiceDocument = SaveNewInvoiceDocument(pdfFilePath)
        If doc IsNot Nothing Then selectedInvoice.DocumentID = doc.ID : selectedInvoice.Save()
        Dim newPdfDocument As PdfiumViewer.PdfDocument = PdfiumViewer.PdfDocument.Load(pdfFilePath)

        If newPdfDocument IsNot Nothing Then
            PdfViewer.Document = newPdfDocument
            PdfViewer.BringToFront()
            isViewPDF = True
        End If
    Catch ex As Exception
        MsgBox(ex.ToString)
    Finally
        If device IsNot Nothing Then device = Nothing
        If pdfDocument IsNot Nothing AndAlso Not pdfDocument.IsClosed Then
            pdfDocument.Close()
        End If
    End Try
End Sub

This code allow user to scan multiple documents, review the scans and save the scanned documents into a pdf document. However, user have to select a scanner device from the commonDialog for each while loop, which is not really efficient.

Here is the code for my SetScannerDevice()

Private Sub SetScannerDevice(Optional runAgain As Boolean = False)

    device = dialog.ShowSelectDevice(WiaDeviceType.ScannerDeviceType, False, False)

    Try
        If device IsNot Nothing Then
            For Each item As [Property] In device.Items(1).Properties
                'Console.WriteLine("Property {0} : {1} = {2}", item.PropertyID, item.Name, item.Value)
                Select Case item.PropertyID
                    Case 3088 'Document Handling Select
                        SetProperty(item, 1)
                    Case 6146 'Intent
                        SetProperty(item, 2)
                    Case 3098 'Page Width
                        SetProperty(item, 8268)
                    Case 3099 'Page Height
                        SetProperty(item, 11693)
                End Select
            Next
        End If
    Catch ex As Exception
    End Try
End Sub

In my attempt to optimize the user experience, I have tried putting the SetScannerDevice outside the while loop, and adjusted the code to only call for dialog.ShowSelectDevice if device = nothing (device not been set). This is to ensure that for each ScanImage called within the while loop, it will scan using the same device and the user can avoid having to select a scanner device for every single scan.

This code works for the first while loop, but on the second loop it gave me the error

WIA_ERROR_PAPER_EMPTY (0x80210003) in image = CType(device.Items(1).Transfer(FormatID.wiaFormatJPEG), ImageFile)

even though

1. my device is still intact
2. my device.item(1) is still intact
3. my scanner feeder is not empty

Anyone has any idea how I can go about fixing this? I am using Brother DS-940DW.