Is UBL-SR-28 a critical error?

Yes, UBL-SR-28 is a critical error that will cause invoice rejection. It must be fixed before submission to ensure your invoice is accepted.

Can UBL-SR-28 be automatically fixed?

Yes, UBL-SR-28 can be automatically corrected. The fix is applied without modifying financial fields.

Error codes · EN16931

UBL-SR-28In your invoicing software

Mandate reference identifier shall occur maximum once

This is the rejection, word for word: „[UBL-SR-28] Your invoice contains multiple Mandate reference identifiers (PaymentMandate/ID). EN16931 allows only one direct debit mandate reference.“

What to have readyNothing. The file has to be re-exported from your invoicing software; we check it again afterwards.

What we doYour invoice contains multiple Mandate reference identifiers (PaymentMandate/ID). EN16931 allows only one direct debit mandate reference.

Choose the rejected invoiceor drop it here

XRechnung XML or ZUGFeRD PDF. Checking is free · corrected file €1.90 · the first every 30 days is free · no sign-up.

What the finding looks likeExample

FindingStructure invalid · UBL-SR-28

Location//cac:PaymentMeans/cac:PaymentMandate/cbc:ID

From youA re-exported file

ThenRe-export

ProofSHA-256 and /verify link after the check