diff --git a/apps/iot/src/iot_endpoint.erl b/apps/iot/src/iot_endpoint.erl
index 8b0bf56..385d9df 100644
--- a/apps/iot/src/iot_endpoint.erl
+++ b/apps/iot/src/iot_endpoint.erl
@@ -180,8 +180,8 @@ handle_event(info, fetch_next, connected, State = #state{tab_name = TabName, cur
 
 %% 收到确认消息
 handle_event(info, {ack, Id}, StateName, State = #state{tab_name = TabName, endpoint = #endpoint{name = Name}, timer_map = TimerMap, acc_num = AccNum, flight_num = FlightNum}) ->
-    lager:debug("[iot_endpoint] endpoint: ~p, get ack: ~p", [Name, Id]),
-    mnesia_queue:delete(TabName, Id),
+    ok = mnesia_queue:delete(TabName, Id),
+    lager:debug("[iot_endpoint] endpoint: ~p, get ack: ~p, delete from mnesia", [Name, Id]),
     Actions = case StateName =:= connected of
                   true  -> [{next_event, info, fetch_next}];
                   false -> []