Devices offline in Google Home

We are using our Homey pro 2019 with our Google Home for a few years now.

As I added some devices in Homey I wanted to resync the connection in the Google Home app. Because that didn’t work I decided to disconnect the Homey from Google Home and reconnect it again.

For a start: this was (or is) a hit and miss. From the ten times I tried to connect to Homey it was unavailable more often than not. When I finally could connect most of the devices are “offline”. Which means using de speech assistent is not possible now and it is a very important part of our smart home.

Edit:
After an hour of trying I tried to connect again and now Google Home seems to see my devices.