Provide the tax basis exactly once

Error FX-SCH-A-000177 Factur-X

Element 'ram:BasisAmount' must occur exactly 1 times.

Mandatory rule: As long as it is violated, the invoice is invalid and will be rejected by validators.
What is wrong

ram:BasisAmount must occur exactly once in ram:ApplicableTradeTax. The element is missing or occurs more than once.

What the rule means

ram:BasisAmount contains the amount used as the basis for the relevant tax calculation. Exactly one occurrence is required to establish that basis unambiguously.

Please provide the tax basis exactly once

The tax basis is missing from the invoice’s VAT section or appears more than once. You can resolve this by having exactly one occurrence there.

What to do
  1. Locate the relevant ram:ApplicableTradeTax.
  2. Check that ram:BasisAmount occurs exactly once within it.
  3. Generate the invoice again and validate it once more.
Technical details

The XPath test uses count(ram:BasisAmount)=1 to require exactly one direct child element named ram:BasisAmount.

Where the rule applies

The rule applies to each ram:ApplicableTradeTax in the document-level VAT breakdown.

Context (rule/@context)
/rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:ApplicableHeaderTradeSettlement/ ram:ApplicableTradeTax
Test expression (assert/@test)
count(ram:BasisAmount)=1