diff --git a/slixmpp_omemo/__init__.py b/slixmpp_omemo/__init__.py
index 4be4f35..e210a8c 100644
--- a/slixmpp_omemo/__init__.py
+++ b/slixmpp_omemo/__init__.py
@@ -206,7 +206,7 @@ class XEP_0384(BasePlugin):
         return self._device_id
 
     def _generate_bundle_iq(self) -> Iq:
-        bundle = self._omemo.public_bundle.serialize(self._omemo)
+        bundle = self._omemo.public_bundle.serialize(self.omemo_backend)
 
         iq = self.xmpp.Iq(stype='set')
         publish = iq['pubsub']['publish']