diff --git a/amcrest_mqtt.py b/amcrest_mqtt.py
index c795eec..33fb3c6 100644
--- a/amcrest_mqtt.py
+++ b/amcrest_mqtt.py
@@ -167,7 +167,7 @@ class AmcrestMqtt(object):
         )
 
         if self.mqtt_config.get('tls_enabled'):
-            self.mqttcnt.tls_set(
+            self.mqttc.tls_set(
                 ca_certs=self.mqtt_config.get('tls_ca_cert'),
                 certfile=self.mqtt_config.get('tls_cert'),
                 keyfile=self.mqtt_config.get('tls_key'),
diff --git a/config.yaml.sample b/config.yaml.sample
index 0a5bbdd..590dedd 100644
--- a/config.yaml.sample
+++ b/config.yaml.sample
@@ -10,7 +10,7 @@ mqtt:
   tls_enabled: False
   tls_ca_cert: filename
   tls_cert: filename
-  tls_key: string
+  tls_key: filename
 
 amcrest:
   hosts: