diff --git a/src/foundation/src/PDFsharp/src/PdfSharp/Pdf.Signatures/PdfSignatureHandler.cs b/src/foundation/src/PDFsharp/src/PdfSharp/Pdf.Signatures/PdfSignatureHandler.cs
index 64c6497f..72e45c90 100644
--- a/src/foundation/src/PDFsharp/src/PdfSharp/Pdf.Signatures/PdfSignatureHandler.cs
+++ b/src/foundation/src/PDFsharp/src/PdfSharp/Pdf.Signatures/PdfSignatureHandler.cs
@@ -153,7 +153,7 @@ internal async Task AddSignatureComponentsAsync()
 
             var annotations = Document.Pages[Options.PageIndex].Elements.GetArray(PdfPage.Keys.Annots);
             if (annotations == null)
-                Document.Pages[Options.PageIndex].Elements.Add(PdfPage.Keys.Annots, new PdfArray(Document, signatureField));
+                Document.Pages[Options.PageIndex].Elements[PdfPage.Keys.Annots] = new PdfArray(Document, signatureField);
             else
                 annotations.Elements.Add(signatureField);