You can choose to invoice multiple shipments on the same Sales Invoice. These shipments can come from one Sales Order, or multiple Sales Orders, as long as the Sell-to Customer and the Bill-to Customer are the same on these Sales Orders as on the Sales Invoice.
Create a Sales Invoice
Make sure all Warehouse Shipments are posted. Then, create a new Sales Invoice.
Get Shipment Line Lines
To add already posted but not invoiced Warehouse Shipment Lines onto the Sales Invoice, select Get Shipment Lines.
Select all Whse. Shipment Lines.
Click Add Lines.
Sales Invoice Lines will be created for the selected Whse. Shipment Lines.