Several AG documents for one purchase invoice

You can issue an expense invoice based on existing warehouse documents, in this case, AG (Acceptance of Goods) or RG (Release of Goods).
The issued documents are located in the Warehouse > Warehouse Documents tab, where you need to select several AG documents using checkboxes and then click on 'Issue an invoice.'

This will generate a document on the Expenses side.

After this action, the program will create an invoice that includes all the products from the AG documents.
The issued invoice will display the AG document that was most recently issued. The created invoice will not update the data of the last AG document.

In the same way, a sales invoice can be issued for several RG documents: https://help.invoiceocean.com/83343404-Issuing-a-sales-invoice-for-several-RG-documents