Google Home: Your client does not have permission to the requested URL

I was so excited to see the communication this week about the integration with Google home and when I finally tried to connect my Sonos system with my my Google Home mini I get the following error:
401.That’s an error.
Your client does not have permission to the requested URL /services/auth/handoffs/auth/complete?state=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&code=eyJhdXRoQ29kZSI6IjA5NDFmNzY2LTRkM2UtNGIzNC05NzU2LTE3MGZhNDdkMTZmYiIsImhvdXNlaG9sZElkIjoiU29ub3NfWW1QUDh0cDFiSFRyTHdGWk4xVUdUblV0bVguSHBUZERHVEJLLXo5MUxEZ2dWa3QiLCJzb25vc0lkIjoiMTExMTQ2MjExIn0%3D&return_url=chromecast://settings/handoff. That’s all we know.

Any ideas? Anyone seen this before?