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