We are trying to use Form.FillField() method to fill the attached PDF form (XFA based).
Thanks for your inquiry. I have tested your scenario with shared document using Aspose.Pdf for .NET 11.4.0 and managed to observe the reported issue. For further investigation, I have logged an issue in our issue tracking system as PDFNEWNET-40424 and also linked your request to it. We will keep you updated via this thread regarding the issue status.
We are sorry for the inconvenience caused.