diff --git a/apps/iot/src/iot_device_sup.erl b/apps/iot/src/iot_device_sup.erl
index 6af3d70..9b9d26d 100644
--- a/apps/iot/src/iot_device_sup.erl
+++ b/apps/iot/src/iot_device_sup.erl
@@ -19,7 +19,7 @@ init([]) ->
     {ok, DeviceInfos} = device_bo:get_all_devices(),
     Specs = lists:map(fun child_spec/1, DeviceInfos),
 
-    {ok, {#{strategy => one_for_one, intensity => 1000, period => 3600}, [Specs]}}.
+    {ok, {#{strategy => one_for_one, intensity => 1000, period => 3600}, Specs}}.
 
 -spec ensured_device_started(UUID :: binary()) -> {ok, Pid :: pid()} | {error, Reason :: any()}.
 ensured_device_started(DeviceUUID) when is_binary(DeviceUUID) ->