Hello - I followed the documentation and set up the NEST HA integration and got the client_id, client_secret and project_id and fed those to the config file and restarted HA. The new device showed up as Nest and while trying to configure the integration and authorize it, I keep getting the below error.
I never provided any redirect_url since that was not specified in the documentation but I tried from both an internal instance of HA as well as an external one.
The funny thing is that it was working fine until today and I had to remove and re-add the integration since I added a couple of new cameras.
Thank you - I had already found a different solution for this issue, not a permanent/desirable solution but it works.
I found on another thread in the forum, apparently this is because Nest revised their authorization protocol recently and hence the integration is broken for everyone who recently installed or re-installed it. the workaround was to put the oauth in testing mode and then everything will work. But you have reauthorize it every 7 days. Hopefully there would be a fix soon.