We've had a number of customers experiencing issues getting their Home Assistant Green up and running - but luckily we've found that it's usually resolved with a factory reset.
The folks at Home Assistant (Nabu Casa) created an easy-to-follow guide here to show you how to factory reset the device: https://green.home-assistant.io/guides/reset/
If you still have problems after a successful factory reset, please contact our support team. There's also a Home Assistant community forum where you can ask questions or search for solutions to common problems.