Can't access, page doesn't exist


When I try to go to the Settings > Widgets page it gives me a blank page, "Sorry, that page doesn’t exist!"
This seems to be an issue with this just one account of mine when I’m logged in, other ones work fine.

I can still create widgets when I go to but not manage them or access, no matter what browser, logging in/out or any other method I try.

Thoughts/Solutions? (Account is @4xac)