User is unable to see vendor names on invoices created by batch invoicing. Previously, the vendors would be listed in the Employee column in Invoice Details > Expense Details. How can this be fixed?

There might have been a change made in Settings. To fix this, go to Settings > Billing & Invoices > Invoice Templates and click Detail for the template you use. Next, click the Layout drop-down and correct the Display Vendor As field of both Time and Expense tabs. When you are done, click Save Changes.