Message

If the group "DIRECT DEBIT" (BG-19) is delivered, the element "Debited account identifier" (BT-91) shall be provided.

Context
(/ubl-invoice:Invoice | /ubl-creditnote:CreditNote)[$supplierCountryIsDE and $customerCountryIsDE]
Test
not(cac:PaymentMeans/cac:PaymentMandate) or (cac:PaymentMeans/cac:PaymentMandate/cac:PayerFinancialAccount/cbc:ID)
Usage
/ ubl:Invoice / cac:PaymentMeans / cac:PaymentMandate / cac:PayerFinancialAccount / cbc:ID
/ ubl:CreditNote / cac:PaymentMeans / cac:PaymentMandate / cac:PayerFinancialAccount / cbc:ID