Can't log into Nest Account When authorising

Hi All

Not sure if anyone else is having this issue. I am trying to authorise my Nest Thermostat on my Vera Gateway and having an issue. I click on the authorise button and it taken me through to the Nest portal where it is asking me to log in. When I use my normal login credentials for my Nest account it fails.

When I just got to and login it works fine.

Is there a reason for this behaviour?