If you see this failure as part of a backup job, then in the Protection task area, select the SQL Server database and click ...

If you see this failure as part of a backup job, then in the Protection task area, select the SQL Server database and click Create recovery point. Choose express full backup. Alternately, you can wait for the next scheduled express full backup to run. 
If this failure occurs as part of a recovery job, then try to recover from another point in time. 
Review the Application Event Viewer logs on the computer running SQL Server for more details. 
Ensure that this database is not already protected by another backup application.