Invoice total VAT amount and Invoice total VAT amount in accounting currency MUST have the same operational sign
PEPPOL-EN16931-R055pxs-taxdata:TaxData/pxs-taxdata:ReportedTransaction/pxs-taxdata:ReportedDocumentnot(cbc:TaxCurrencyCode) or (cac:TaxTotal/cbc:TaxAmount[@currencyID=normalize-space(../../cbc:TaxCurrencyCode)] <= 0 and cac:TaxTotal/cbc:TaxAmount[@currencyID=normalize-space(../../cbc:DocumentCurrencyCode)] <= 0) or (cac:TaxTotal/cbc:TaxAmount[@currencyID=normalize-space(../../cbc:TaxCurrencyCode)] >= 0 and cac:TaxTotal/cbc:TaxAmount[@currencyID=normalize-space(../../cbc:DocumentCurrencyCode)] >= 0)