Final account assignment quantity exceeded by &1 &2

What causes this issue?

During invoice entry you want to post a quantity to an account
assignment item which has a <DS:DE.AA_FINAL_IND>final account assignment
indicator</> in the purchase order to which it is referenced. The
quantity you entered exceeds the open quantity for the account
assignment item by &V1& &V2&.
When calculating the <DS:DE.AA_OPEN_QTY>open quantity</> that you may
currently post to the item with a final account assignment, the system
calculates the difference between the final account assignment quantity
and the invoice quantities that have already been posted to the account
assignment item.
When calculating the quantity difference, the system only includes
quantities from posted incoming invoices, and does not take parked
invoice quantities into account. However, you can specify in Customizing
for <ZK>Public Sector Management</> that the system should take into
account invoices with the status <ZK>parked as complete</> and <ZK>
parked released</> when calculating the final account assignment
quantity. Then the system also includes invoices with those two statuses
when calculating the open quantity.

System Response

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

How to fix this error?

Reduce the quantity that you are posting to the account assignment item
with a final account assignment by at least &V1& &V2&.

Procedure for System Administrators

Error message extract from SAP system. Copyright SAP SE.