How to disallow users to amend VAT / Tax Code on existing PO line after receipt creation
Summary:
When PO is approved, that will book the obligation (with Net amount and Nonrecoverable tax amount) in BC as well encumbrance accounting. Further when the Receipt is created that will reverse (-) the obligation (with Net amount and Nonrecoverable tax amount) into BC and encumbrance accounting. At this point the obligation balance is zero in both BC and encumbrance accounting for the PO Line as it is completely fulfilled.
Once the Invoice is received from suppplier with zero or recoverable VAT Code, Requestor changes the vat code on existing PO line [Closed for receiving] from Non recoverable tax code to zero tax code / recoverable tax code by creating a change order. This will trigger the reversal of the obligation earlier booked for Nonrecoverable tax amount. The results in negative obligation balance for that PO line in both Budgetary control as well as GL encumbrance accounting.