How to fix PDF-06
The file specification has no valid /AFRelationship
A check of the PDF of a ZUGFeRD or Factur-X invoice, not of its XML. It runs when you upload a PDF; the embedded XML then gets the XSD and EN 16931 checks (XRechnung: also the KoSIT rules). Check your PDF with the ZUGFeRD validator or the Factur-X validator. What the PDF check covers.
What this rule checks
PDF/A-3 requires every embedded file to state its relationship to the document (/AFRelationship). ZUGFeRD and Factur-X allow Alternative, Source or Data for the invoice XML (Alternative for the EN 16931 based profiles in Germany, Data or Source in France).
How to fix it
Set /AFRelationship /Alternative (or /Source, /Data) on the file specification of the invoice XML.
Related rules
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