[IBR-155-OM] - If invoice transaction type (BTOM-001) is export invoice (XXXXXX1XXXXXXXXXXXXX) and atleast one VAT exemption reason code (IBT-121) is 'Export of service' then Service Type (BTOM-015) must be provided from the codelist for Type of Services (CL-12-OM).
IBR-155-OMubl:Invoice | cn:CreditNotenot($isExport and $lines[cac:Item/cac:ClassifiedTaxCategory/cbc:TaxExemptionReasonCode ='VATZR-OM-09']) or $lines[cac:Item/cac:CommodityClassification/cbc:ItemClassificationCode]