All I can think is you need a Content-Length header? It's worth checking out https://www.espruino.com/IoT+Services for some HTTP post examples.
Content-Length
That Fixed it!
@Gordon started
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
All I can think is you need a
Content-Length
header? It's worth checking out https://www.espruino.com/IoT+Services for some HTTP post examples.