Follow up: I was able to reach someone at Google/Nest fairly easily. She
directed me to hold the Nest Protect that would not join within 1 foot
of a unit that was already connected. Previously I had been several feet
away, so I got up on a step stool...
I am having the same problem. 4 of the 5 were able to connect to the new
wifi and each other (as seen in the Nest app) but the 5th continually
gives error/unable to connect message. I have done the reset. Removed it
from my account, trying to re-add ...
