Got the same problem. Wants me to revoke one of three "devices":-
laptop
mobile
web (which is my laptop browser)
Why is my laptop and my browser counted as two separate devices?
If I delete my laptop, I cant use my browser. If I delete my 'web' (browser), I cant get onto the web. If I delete my mobile (linked to my account) and can no longer see my shopping list when I'm at the office, I may as well leave my mobile at home and take a hand written shoppin list with me.
Any suggestions as to how I / we can get around the problem?