You'll see this message when your account has moved to the Free plan and you have more than 3 lists:
This list is read-only since Free Plan allows max 3 lists.
No. All your lists and tasks are still there. You can open and read them, but you can't change them or move tasks out of them.
Your 3 oldest lists stay editable. Lists shared with you count towards the 3.
Usually a trial ended, a payment failed or a subscription was cancelled. If you think that's a mistake, check Subscription in the menu, or write to us from Support.
If a payment fails, WeGoDoo shows you a message so you can update your card first.