If you have several tabs open in a browser while you are navigating through your Keep&Share account you may suddenly see a message notifying you that you are either logged out of your account or have switched to a different Keep&Share account.
For the "You have logged out" message you have logged out of your account in one tab and tried to access something in the same account in a different tab.
For the "You have changed Keep&Share accounts" message you have logged out of one Keep&Share account in one tab, logged into a different Keep&Share account, and then tried to access something from the first account in a different tab.
The purpose of both of these messages is to prevent the loss of any data in your accounts. If you try to enter something into your account and you're not logged into that account then none of your changes will be saved and you will lose any changes you tried to make.
To make edits to your account all you need to do is log into the account indicated by the "logged out" message that you see. Once you have logged back into the account the message will disappear from any affected tabs, and you may resume your work.