CSharp Docx Bookmarks mit Microsoft Interop füllen und entfernen

while (bookmarkRange.InlineShapes.Count > 0)
{
    bookmarkRange.InlineShapes[1].Delete();
}

private void Convert()
    {

        // Exemplarische Pfade
        string wordTemplatePath = "C:\\Users\\Name\\Desktop\\Neuer_Ordner\\Template.docx";  

        var word = new Microsoft.Office.Interop.Word.Application();
        var template = word.Documents.Open(wordTemplatePath);
        word.Visible = false;

        // Für jede Zeile
        for (int i = 2; i <= totalRows; i++)
        {
            // Bookmark
            Microsoft.Office.Interop.Word.Bookmark bookmark = template.Bookmarks["Signatur"];  

            // Position
            Microsoft.Office.Interop.Word.Range bookmarkRange = bookmark.Range;

            while (bookmarkRange.InlineShapes.Count > 0)
            {
                bookmarkRange.InlineShapes[1].Delete();
            }

            // Pfad
            string signatureFileName = Person + ".png";  
            string signatureFilePath = Path.Combine(Path.GetDirectoryName(wordTemplatePath), signatureFileName);

            // Hinzufügen
            bookmarkRange.InlineShapes.AddPicture(signatureFilePath);

            template.Fields.Update();
            string pdfDocName = $@"{tbOutputPath.Text}\\Doc_{name}_{zeitpunkt.Date:dd.MM.yy}.pdf";  
            if (template != null)
            {
                template.ExportAsFixedFormat(pdfDocName,
                WdExportFormat.wdExportFormatPDF);
            }

        }
        template.Close();
        word.Quit();
    }