No purchase order was found for GR document

What causes this issue?

The system cannot find a purchase order for the GR document entered.
This may be due to one of the following reasons:
The purchasing department has not defined GR-based invoice verification
for any items of the purchase order.
You have entered an item of the GR document number. No goods-receipt-
based invoice verification had been defined for the relavant order item.
You entered the wrong GR document number.
GR document &V1& was not posted in &V2&.
Check the GR document number, the item and the year, and make any
necessary corrections.
If everything was correct, you cannot enter the invoice using the GR
document number. Proceed as follows:
If the invoice contains a PO no., enter this as a selection criterion.
If the invoice does not contain a PO number, position the cursor on the
field <LS>Purchase order</> and press F4. A window will appear in which
you now enter the supplier shown in the invoice. You can then display
all purchase orders for this supplier for the materials listed in the
invoice. By referring to other information contained in the invoice
(such as quantity and price), you can find the correct purchase order
and then select it.

Error message extract from SAP system. Copyright SAP SE.