Cant delete linked service from Google Home

I have about 14 Google Home-devices. 2 years ago something went wrong with the linked service to HA by Nabu Casa. I cant unlink the service anymore and I do have a lot of ghost entities, 185 of them. On the page where to reconnect or unlink the service it says I have 1674 devices. What? The Google Home app is slow and krasches. I have deleted other familymembers, deleted all homes/houses, clear storage for the app on my android. Even reinstalled the application. Stoped the integration from Home Assistant.
Still, the linked service cant be unlinked. Nor syncing devices.

Any idea on how to proceed?

if you only have one home user, deleting the home would remove everything and you can start from scratch with a new home.

As soon as I create a new home those linked entities are present again and the link to HA by Nabu Casa is still linked. If I could get rid of that link.