diff --git a/local/lib/org-x/org-x.el b/local/lib/org-x/org-x.el
index b3210d0..c540c95 100644
--- a/local/lib/org-x/org-x.el
+++ b/local/lib/org-x/org-x.el
@@ -1965,7 +1965,7 @@ and slow."
                  (org-ml-unixtime-to-time-long)
                  (org-ml-build-timestamp!)
                  (org-ml-to-string)
-                 (org-ml-build-node-property org-x-prop-created))))
+                 (list org-x-prop-created))))
     (org-ml-update-this-headline*
       (org-ml-headline-map-node-properties* (-snoc it np) it))))