So, our nest thermostat's wifi broke with only 6 months of use. We got the replacement today. Our nest app is controlling it fine but alexa is still saying can't find it.
I thought I have to disable the skill which means my husband has to login to my alexa app again with his nest credentials, but not AFTER giving me a hard time. Ugh.
Anyway, only then did it prompt me to discover devices. It's working now but for those that had to go through with it.
You don't need to disable the nest skill for it to work. All you have to say is:
Alexa discover devices.
Ugh, wish I'd known that before my husband annoyed me.