Error validating user
You can check the official documentation on How-To: Handle expired access tokens by Facebook itself.
Note: In some cases in the development environment, users have the Remove offline_access permission enabled.
Access tokens are items used by applications which are used to make API requests on behalf of the user.
Mainly, the access token represents the authorization of a specific application so it can either authorize the login or access some information of the user.
Make sure that you have your username and password at hand because you may be asked to enter it.Normal users may experience this error message when trying to log into the messenger or while switching between different accounts.This is no more than a mere bug in your android device.I've tried creating an app password in the MFA configuration settings and using that, but it's also failing to login.Unfortunately, this is expected with MFA and Azure CLI.