Why are my time entries locked?

User is reviewing time entries and while attempting to make edits, is prompted that the time entries are locked even though they have not been billed. Or some time entries appear grayed out or disabled on the grid indicating that those entries are locked for invoicing. These entries are locked because you might have opened multiple CORE windows and have a billing session on or another CORE user is working on them. If you exit the Invoices screen and refresh the time entries, you should be able to release the entries and edit them as needed.