Nest Protect devices after adding home

Does anyone know how to get Nest Protect devices added to another location, but using the same Nest account into HA? I have two homes (one I am selling), and added Nest smoke/CO2 sensor to the new house, but they are not showing in HA as the old ones are.

When going into my Nest account online, I can toggle between the homes.

Anyone? I am about to remove the configuration and re-add. I am not confident this will work.