If rendered sessions aren't appearing in Manage Billing, you can check your patient's authorization status - whether it is Active or in a Placeholder state. If it is the latter, the sessions won't appear for billing, even though they have been rendered and timesheets have been submitted. 

Don't worry, this doesn't affect your timesheet submission. It just prevents sessions from appearing in billing until you toggle off the placeholder status. You can check this in the Authorization History.