Invoice line total amount only once

Error FX-SCH-A-000382 Factur-X

Element 'ram:LineTotalAmount' may occur at maximum 1 times.

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

ram:LineTotalAmount occurs more than once in ram:SpecifiedTradeSettlementLineMonetarySummation.

What the rule means

ram:LineTotalAmount represents the total amount of the invoice line. Multiple occurrences would provide more than one value for this amount in the same summation.

Please include the invoice line total amount only once

The total amount appears more than once in an invoice line’s settlement. Each invoice line may contain this element there no more than once.

What to do
  1. Look for repeated ram:LineTotalAmount elements in ram:SpecifiedTradeSettlementLineMonetarySummation.
  2. Make sure this element occurs there no more than once.
  3. Generate the invoice again and validate it.
What it looks like
✗ Triggers the message 
<ram:SpecifiedTradeSettlementLineMonetarySummation>
  <ram:LineTotalAmount>100.00</ram:LineTotalAmount>
  <ram:LineTotalAmount>120.00</ram:LineTotalAmount>
</ram:SpecifiedTradeSettlementLineMonetarySummation>
✓ Correct 
<ram:SpecifiedTradeSettlementLineMonetarySummation>
  <ram:LineTotalAmount>100.00</ram:LineTotalAmount>
</ram:SpecifiedTradeSettlementLineMonetarySummation>
Technical details

The XPath counts ram:LineTotalAmount elements in the current ram:SpecifiedTradeSettlementLineMonetarySummation; the test passes when there is at most one.

Where the rule applies

The rule applies to the monetary summation in an invoice line’s settlement and checks ram:LineTotalAmount there.

Context (rule/@context)
/rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:IncludedSupplyChainTradeLineItem/ ram:SpecifiedLineTradeSettlement/ram:SpecifiedTradeSettlementLineMonetarySummation
Test expression (assert/@test)
count(ram:LineTotalAmount)<=1