Underfloor Heating Thermostat "no response"
I have just had electric underfloor heating installed with a Wifi thermostat. The thermostat is controlled using the Tuya Smart app but for some reason it's showing "no response" in Homekit/Homebridge. 
I also have some electric radiators connected via a different wifi thermostat, also controlled using the Tuya Smart app which is working fine in Homekit/Homebridge.
Any ideas what might be causing this new wifi thermostat to be unresponsive? I'm just surprised that it works in the Tuya Smart app but not then via Homebridge to HomeKit.
Thanks,
Anthony 