Hi looks ok, but the info you provided is very limited. Please check youtube . Search "mqtt thingworx" and watch my two great videos how to start and configure MQTT with Thingworx. Works for me perfectly with MOSQUITTO. Also please check the mosquitto.log to see, that TWX subscribed and get updates of the messages. Additionally please be aware of TWX caching. Sometimes you need to hit the "refresh value" button to see changes in the developer part of ThingWorx.