Can not connect to Bluetooth for initial set up

[DDECarson]

I have rebooted and updated everything. My Nest thermostat is connected to WiFi  but i can not add it to the app as it does not appear in my list of bluetooth devices to connect too. Yes i swithced my bluetooth on and off and yes i rebooted and yes i updated the app. Other people seemed to have had issues with this but  i could not find a successful resolution to the problem. Once i am over this stage the rest seems a doddle but this bit has me stumped

[David_K]

You won't see the thermostat in Bluetooth settings on your phone as that's not how it works.

Firstly, Which model of thermostat do you have? You can check here:

How to tell which Nest thermostat you have - Google Nest Help

I'm assuming your thermostat was previously showing in the app, but now is not?