Why fail to delete those watermark added as textstamp and imagestamp?

Hi, Support:

I use Pdf.pages(p).AddStamp(TextStamp) and Pdf.AddStamp(ImageStamp) to create watermarked pdf, and then, using the following code to remove them,but fail:

Dim Pdf As New Aspose.Pdf.Document(PdfFile)
Dim Pages As Integer = Pdf.Pages.Count
Dim PdfContentEditor As PdfContentEditor

For p As Integer = 1 To Pages
    Dim TmpPdf As New Aspose.Pdf.Document()
    TmpPdf.Pages.Add(Pdf.Pages(p))
    Dim WatermarkAnnotations = TmpPdf.Pages(1).Annotations

    For Each CA As WatermarkAnnotation In WatermarkAnnotations
        If CA.AnnotationType = AnnotationType.Watermark Then
            TmpPdf.Pages(1).Annotations.Delete(CA)
        End If
    Next

    PdfContentEditor = New PdfContentEditor()
    PdfContentEditor.BindPdf(TmpPdf)

    For Each Stamp As StampInfo In PdfContentEditor.GetStamps(1)
        PdfContentEditor.DeleteStampById(Stamp.StampId)
    Next

    PdfContentEditor.Save(AppPath & "\Tmp.pdf")
    PdfContentEditor.Dispose()
    PdfContentEditor = Nothing

    TmpPdf = New Aspose.Pdf.Document(AppPath & "\Tmp.pdf")
    Pdf.Pages.Delete(p)
    Pdf.Pages.Insert(p, TmpPdf.Pages(1))
Next

Pdf.Save(PdfFile)

Also, the above codes can not remove text/image watermark added by Adobe.
Please tell me what’s wrong about this ,and what is the right one to reach it.
Three Sample Pdf Files:
图片水印.pdf (146.4 KB)

文字水印.pdf (185.5 KB)

文字水印+图片水印.pdf (270.1 KB)

@ducaisoft

We have opened the following new ticket(s) in our internal issue tracking system and will deliver their fixes according to the terms mentioned in Free Support Policies.

Issue ID(s): PDFNET-55861

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