diff --git a/xos/synchronizer/event_steps/onu_event.py b/xos/synchronizer/event_steps/onu_event.py
index 4b770a1..d205a59 100644
--- a/xos/synchronizer/event_steps/onu_event.py
+++ b/xos/synchronizer/event_steps/onu_event.py
@@ -59,6 +59,6 @@
             att_si.authentication_state = "AWAITING"
         else:
             self.log.warn("onu.events: Unkown status value: %s" % value["status"], value=value)
-        att_si.save(always_update_timestamp=True)
+        att_si.save_changed_fields(always_update_timestamp=True)