At most one seller item description

Error FX-SCH-A-001039 Factur-X

Element 'ram:Description' 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:Description occurs more than once within ram:ItemSellerTradeParty.

What the rule means

The XML structure allows at most one ram:Description element in this seller-item context. Multiple descriptions do not conform to the specified structure.

Please use no more than one description for the seller item

More than one ram:Description element is included for the seller item on this invoice line. The XML structure allows no more than one here.

What to do
  1. Find all ram:Description elements in ram:ItemSellerTradeParty.
  2. Make sure this element contains no more than one ram:Description.
  3. Regenerate the invoice and check it again.
What it looks like
✗ Triggers the message 
<ram:ItemSellerTradeParty>
  <ram:Description>Article A</ram:Description>
  <ram:Description>Article A</ram:Description>
</ram:ItemSellerTradeParty>
✓ Correct 
<ram:ItemSellerTradeParty>
  <ram:Description>Article A</ram:Description>
</ram:ItemSellerTradeParty>
Technical details

The rule counts the direct ram:Description elements in context and requires their number to be no greater than one.

Where the rule applies

The rule applies to ram:ItemSellerTradeParty within the agreement for an invoice line.

Context (rule/@context)
/rsm:CrossIndustryInvoice/rsm:SupplyChainTradeTransaction/ram:IncludedSupplyChainTradeLineItem/ ram:SpecifiedLineTradeAgreement/ram:ItemSellerTradeParty
Test expression (assert/@test)
count(ram:Description)<=1