The credit account identifier is not a valid IBAN for a SEPA transfer
When `Payment means type code` (BT-81) is 58 (SEPA credit transfer), `Payment account identifier` (BT-84) must be a correct IBAN — both its shape and its check digits.
Only the issuer holds this value: Factlint reports it and never fabricates it. Test your invoice to find out whether it is affected.
Why this error happens
The rule recomputes the check digits, it does not merely look at the shape. It therefore catches the transposed digit in a hand-typed IBAN, which nothing else detects before the bank rejects the payment. Presentation spaces are stripped before the check: formatting is never what fails.
How to fix it
Fix the IBAN in your bank master data. Factlint never writes it, even when it is supplied explicitly: the IBAN is named as a financial field (rule 1), and an automatic correction of payment details is exactly the write a fraudster would try to induce.
Severity returned by the rule set
The XRechnung package classifies this rule as `warning` — a doubtful IBAN does not stop the document from being formally compliant. An in-scope warning still rules out a “compliant” verdict — at best the invoice comes out as `needs_input`. The bank, for its part, will not return a warning.