Related article: [Admin report] Billing Case Note Details
As a best practice, we recommend that you run the Billing Case Note Details report (Reports tab - Billing Reports sub-tab) to find case notes that are in draft status in order to get them submitted and ready for invoicing.
Enter a Start Date, Draft for Case Note Status, and select the Customer Account(s) to narrow down your results depending on the invoice (Case or EDI) you plan on creating:
You can enter other parameters if you want to further narrow down the results.
Once the draft case notes are submitted, you can proceed with creating the invoice.