diff --git a/fab_access/mqtt_client.py b/fab_access/mqtt_client.py
index 9062e5f..337de9b 100644
--- a/fab_access/mqtt_client.py
+++ b/fab_access/mqtt_client.py
@@ -25,7 +25,7 @@ class MqttHandler:
             else:
                 print('Failed to connect, return code %d\n', rc)
 
-        MqttHandler.client = mqtt_client.Client(Config.mqtt_client_id+get_random_string(5))
+        MqttHandler.client = mqtt_client.Client(Config.mqtt_client_id+MqttHandler.get_random_string(5))
         MqttHandler.client.username_pw_set('admin', 'user')
         MqttHandler.client.on_connect = on_connect
         MqttHandler.client.username_pw_set(Config.mqtt_user_name, Config.mqtt_password)