Hi I've just received my NEW home assistant green.
All plugged in download app but all i get is a login in page as if i have logged in before any help would be great
Probably not so new...
You can reset the Green by following the procedure here: https://support.nabucasa.com/hc/en-us/articles/25161225495837-Resetting-Home-Assistant-Green
You should afterwards get the onboarding screens...
As Chris above says, or try to access Your Green from a Browser, from i.e a laptop/pc ( Not HA-App )