diff --git a/NetworkLock.cpp b/NetworkLock.cpp
index 21ed905..a3e2439 100644
--- a/NetworkLock.cpp
+++ b/NetworkLock.cpp
@@ -21,6 +21,8 @@ NetworkLock::NetworkLock(Network* network, Preferences* preferences, char* buffe
     _configTopics.push_back(mqtt_topic_config_auto_lock);
     _configTopics.push_back(mqtt_topic_config_single_lock);
 
+    memset(authName, 0, sizeof(authName));
+
     _network->registerMqttReceiver(this);
 }
 
diff --git a/NetworkOpener.cpp b/NetworkOpener.cpp
index 1daa850..a0d1d0a 100644
--- a/NetworkOpener.cpp
+++ b/NetworkOpener.cpp
@@ -17,6 +17,8 @@ NetworkOpener::NetworkOpener(Network* network, Preferences* preferences, char* b
     _configTopics.push_back(mqtt_topic_config_led_enabled);
     _configTopics.push_back(mqtt_topic_config_sound_level);
 
+    memset(authName, 0, sizeof(authName));
+
     _network->registerMqttReceiver(this);
 }