Message

Total amount for payment MUST be equal to the tax inclusive amount minus the prepaid amount.

Context
cac:LegalMonetaryTotal
Test
not(cbc:PayableAmount) or $payableAmount = u:twodec($taxInclusiveAmount) - u:twodec($prepaidAmount)
Usage
/ ubl:OrderResponse / cac:LegalMonetaryTotal / cbc:PayableAmount