Enter the reference nota fiscal in header text (GOTO HEADER)

What causes this issue?

For Nota Fiscal based on purchase order items without goods receipt
based invoice verification flag a reference is mandatory.

The system issues an error message and will not allow you to continue with this transaction until the error is resolved.

System Response

How to fix this error?

Please insert the reference Nota Fiscal in the header text of the
invoice

Error message extract from SAP system. Copyright SAP SE.