In the general scope of things, green is good! It means the UI is up and running. It's possible the hub changed IP addresses. Is the hub set to DHCP and does it have an address reservation in your router's DHCP table?
Are you able to get to the diagnostics tools page on port 8081?
HTTP://[your-hubs-IP-here]:8081
Take a look here also... Cant get my hub to open - #9 by 672southmain
You can also try the "reset network settings" button on the bottom - Network Setup - Hubitat Documentation
