I am attempting to integrate my NEST devices with Home assistant so following these instructions: https://www.home-assistant.io/integrations/nest/
I have created a google cloud project, enabled "Smart Device Management" and "Cloud Pub/Sub" APIs, configured OAuth Consent screen which is now in production and configured OAuth Application Credentials - which generated a client ID and Secret.
I have also paid the $5 for the device access console so can access this screen:
However when I go through the process of creating a project, inputting the OAuth Client ID and submitting, it will try for a few minutes and then get the following error:
Really not sure what I am doing wrong. Any help would be greatly appreciated.