Price Tolerance

We have recently implemented a new system to generate requisitions which would then interface into Oracle and get approved and convert into a PO (In Oracle). The items are housed in this new system along with the pricing. We have created equivalent items in Oracle as non inventory items without any pricing. We have a price tolerance by percentage in place.Things work fine if we dont change any price while converting this requisition into a standard PO, however, if we update the price for an item in the PO then we get a price tolerance error if the changed price