fatalEN 16931syntax binding ruleUBL
Due Date shall occur maximum once
'Due Date' appears more than once, and this profile allows it at most once.
Keep the single correct 'Due Date' 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 /ubl:Invoice | /cn:CreditNote
(count(cac:PaymentMeans/cbc:PaymentDueDate) <=1)