Fixed broken link resulting from heading change

Author: DENKEN02MSFT

articles/iot-hub/troubleshoot-error-codes.md

@@ -128,7 +128,7 @@ This error can occur because the [SAS token used to connect to IoT Hub](iot-hub-
 
 Some other possibilities include:
 
-* The device lost underlying network connectivity longer than the [MQTT keep-alive](../iot/iot-mqtt-connect-to-iot-hub.md#default-keep-alive-timeout), resulting in a remote idle timeout. The MQTT keep-alive setting can be different per device.
+* The device lost underlying network connectivity longer than the [MQTT keep-alive](../iot/iot-mqtt-connect-to-iot-hub.md#default-keep-alive-time-out), resulting in a remote idle timeout. The MQTT keep-alive setting can be different per device.
 * The device sent a TCP/IP-level reset but didn't send an application-level `MQTT DISCONNECT`. Basically, the device abruptly closed the underlying socket connection. Sometimes, this issue is caused by bugs in older versions of the Azure IoT SDK.
 * The device side application crashed.