ram:ID no more than once

Error FX-SCH-A-001147 Factur-X

Element 'ram:ID' 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:ID occurs more than once in ram:IncludedReferencedProduct. This element may appear no more than once in this scope.

What the rule means

ram:ID contains an identifier for the referenced product. The rule limits the number of these identifier elements to one at most.

Please include `ram:ID` no more than once in the referenced product

ram:ID appears more than once in the referenced product. The element may appear no more than once in this section.

What to do
  1. Find ram:IncludedReferencedProduct in the invoice line’s product details.
  2. Check the ram:ID elements inside it and remove any occurrences beyond the first.
  3. Generate the invoice again and validate it once more.
What it looks like
✗ Triggers the message 
<ram:IncludedReferencedProduct>
  <ram:ID>1</ram:ID>
  <ram:ID>2</ram:ID>
</ram:IncludedReferencedProduct>
✓ Correct 
<ram:IncludedReferencedProduct>
  <ram:ID>1</ram:ID>
</ram:IncludedReferencedProduct>
Technical details

The test counts the direct ram:ID elements in ram:IncludedReferencedProduct and requires no more than one.

Where the rule applies

The rule applies within ram:IncludedReferencedProduct, which appears in the product details of an invoice line.

Context (rule/@context)
/rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:IncludedSupplyChainTradeLineItem/ ram:SpecifiedTradeProduct/ram:IncludedReferencedProduct
Test expression (assert/@test)
count(ram:ID)<=1