Ethernet not working on Vero 4k+

i have always used the wifi on it and it worked.
i had my google chromecast connected to ethernet so swapped them over, and ethernet isnt working
any help would be appreciated

How do you determine that

i feel like a bit of an idiot now. i had tried everything from new cables to turning it on and off to installing everything again, we had a powercut last night and that fixed the issue