Hi @aguspg, thanks again for the follow up - but I’m really confused. Firstly, my POSTMAN setup looks nothing like yours, and doesn’t have a preview button. Mine is based on the example by @ScruffR - shown on this post. Also, if the arg=led, what is the parameter for turning it on or off? Lastly, by the Ubidots “event body”, do you mean the field called “Payload”?