Found this post from beginning of this year (https://www.googlenestcommunity.com/t5/Nest-Protect/Nest-protects-disappeared-from-app/m-p/573502/th...) with same issue.
I don't open the Nest app often, I only have 2 Nest Protects so there's really not much to check on, unless maybe a battery warning. I noticed one of my Protects having a Yellow circling ring, so went to open the Nest app yesterday to investigate and it wanted me to log in. Not unusual as apps from time to time seem to log out. But then it wanted to have me to setup my "home" again from scratch and it did not show my 2 Protects afterwards.
I was able to see in Messages that the last sound check was back in May, so not sure if thats when they "disappeared".
Now the app wants me to Factory Reset the devices in order to add them back.
WHY are they even gone out of the app in the first place???
I am the only owner/user, i only have 1 home. I have not removed or deleted anything with the Nest App.
The ONLY thing I can think of is I know I had the Google Home app still on my phone and removed it as I wasn't using it. If this is the cause then that's crappy on Google's part to have them tied together.
