Flatten not working

Hi
I am using the following code sample on a PDF I already have. The pdf has form fields in it, already containing text. When I use this code, it does nothing, it simply copies the PDF with the for fields unchanged.
The fields do appear in the document.form.fields property (in fields and childFields)
How can I solve this ?

[Visual Basic]
' Create a merge document with your PDF containing form fields
Dim document As MergeDocument = New MergeDocument("C:\AcroForm.pdf")

'Set FormFlattening property of the document
document.FormFlattening = FormFlatteningOptions.Default

'Save the document
document.Draw("C:\AcroForm_Flattened.pdf")

Hello,

We did some testing on our end by setting FormFlatteningOptions to Default we are able to remove all the fields from the form field list of the output PDF.

Can you please send over the input PDF document which you are using for merging and flattening and the exact build number of the dll file to our support team at: support@cete.com so that they can look into it further?

Thanks,
ceTe Software Support Team.

Hello,

The PDF document in question is a XFA/dynamic PDF form generated in Adobe Live Cycle. This type of PDF forms are not fully supported in our API. This is the reason why the form flattening is not working as expected. Only simple merging of an XFA PDF is supported. The static PDF forms are fully supported and form flattening will work correctly.

Thanks,
ceTe Software Support Team.