Reinstalling Nest Integration - Failing miserably

So my HA instance failed on me a few weeks ago and i got around to restoring it, however the Nest integration wouldn’t work.
I have tried everything (apart from a fresh install of HA).
I reset the Google side by making a new project but when it comes to adding Nest, when it asks to choose an account i just get the following error

Something went wrong
Please contact the developer of this app if the issue persists.

I have removed everything I can think of on the HA side relating to google and when I restart it still automatically rediscovers Nest.

I followed an excellent youtube video by MostlyChris, and the part I don’t have is the Add Application Authentication.

Anyone out there can give me some advice before i pull what hair i have left out of my head.

Hello I spent hours last week trying to solve. Watched the video twice. Deleted the application and project twice. Got it correct on my third attempt. Wrote down the ids and projects very carefully. Used wrong id and in the wrong place! I never read instructions properly! Don’t be afraid to restart

I have restarted and still wont work. I’m not getting the option to authenticate :frowning:

I had to delete the application credentials. When I did that the integration allowed me to re input my new and correct (on the third time of trying) credentials. It was quite a complicated process.