fatalEN 16931syntax binding ruleUBL
Referenced purchase order line identifier shall occur maximum once
'Referenced purchase order line identifier' appears more than once, and this profile allows it at most once.
Keep the single correct 'Referenced purchase order line identifier' and delete the rest. Repeating an element that the semantic model treats as singular is usually a serialiser writing every value it has instead of choosing one.
UBL — context cac:InvoiceLine | cac:CreditNoteLine
(count(cac:OrderLineReference/cbc:LineID) <= 1)