Encountering issue when trying to 'Authorize with Trello', is there something I'm missing?

[Jake Mercer]

I'm following the directions laid out here:
https://blog.trello.com/trello-for-google-hangouts-chat

When clicking 'Authorize with Trello' I'm taken to a page that gives me the following message:

Uh oh! There was an error linking your accounts.