Allow me to share some information on how to modify the customer's name to the invoice. You can manually edit the name by going to the Invoices tab and clicking the drop-down arrow, and selecting View/Edit.
Here's how:
Select the Sales menu/.
Navigate the Invoices tab.
Locate the invoice then click the drop-down from the Actions column.
Choose View/Edit.
However, if you're trying to add a customer's name to invoices, you can click the Add New button from the invoice page.