fatalEN 16931syntax binding ruleUBL
Mandate reference identifier shall occur maximum once
'Mandate reference identifier' appears more than once, and this profile allows it at most once.
Keep the single correct 'Mandate reference 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:PaymentMeans
(count(cac:PaymentMandate/cbc:ID) <= 1)
Nothing is stored, and the whole invoice is checked, not just this rule. A PDF only works if it is Factur-X / ZUGFeRD — a PDF with the invoice XML inside it.