When the licence policy on an account lapses, all users will see the Licence Violation error.
It is still possible to log into the account and review the projects. This would be in a read only view.
Please check the Administration > Licence area for further details.
If the warning relates to active users, it is possible to bring the licence back in line. Reduce the number of active users via Administration > Users and inactivating or archiving active users.
If you require additional licences, or If you are seeing a licence violation, and believe this to be in error, please contact our helpdesk to discuss your requirements.