The legacy eagle has a local webserver to access your energy data. The cloud server for the original eagle is no longer operational.
To access your eagle locally, make sure you're on a computer that is on the same network as the EAGLE. Then open a browser to the link on the back of the device that looks something like this: http://eagle-XXXXXX.local/ Where XXXXXX is the Cloud ID of your device.
If that doesn't work, you can also try getting the IP address of the eagle on your local network through your router's admin page and try browsing to that.
The original energyvue app (aka Legacyvue), also has a 'local' mode you can select by toggling a button on the bottom of the login page. Your phone will need to be on the same network as the eagle.
When you are logging in locally, the username and password that you used to login through the cloud will not work. Instead for the username use the 6 digit CloudID, and for the password use the 16 digit install code. Both are located on the bottom of the EAGLE.
For more details:
Legacy User Manual: https://rainforestautomation.com/wp-content/uploads/2015/06/EAGLE%20User%20Manual%202.2.2.pdf