diff --git a/src/PDFDoc.php b/src/PDFDoc.php
index f6f3c29..d8c880c 100644
--- a/src/PDFDoc.php
+++ b/src/PDFDoc.php
@@ -366,7 +366,7 @@ protected function _generate_signature_in_document() {
             $page_obj["Annots"] = new PDFValueList();
 
         $annots = &$page_obj["Annots"];
-        $page_rotation = $page_obj["Rotate"]??0;
+        $page_rotation = $page_obj["Rotate"]??new PDFValueSimple(0);
 
         if ((($referenced = $annots->get_object_referenced()) !== false) && (!is_array($referenced))) {
             // It is an indirect object, so we need to update that object