For fiscal purposes it is not possible to create a consolidated invoice replacing invoices of sales already closed in your account.
But you can generate a payment statement grouping all invoices completed over a predetermined period of time for a specific customer.

In the 'Apps' section of our account, install the 'Combined invoice' application (Premium option required).
You also need to install the 'PDF Documents' application (more information).

Configure the 'Combined invoice' application :
– select the invoice template that will be used from the 'PDF Documents' application,
– enter a header content for the invoice statement document.

In each customer form, you will find an 'Action' drop-down menu.
Choose 'Combined invoice'.
Select the start and end dates.
The application will generate in a single PDF file an invoice statement with all invoices attached for the period.