PDF-09warning
How to fix PDF-09
The MIME type of the invoice XML is not text/xml
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
ZUGFeRD and Factur-X give the invoice XML the MIME type text/xml. Another value (for example application/xml, or a name with a stray #) is accepted by most receivers, but does not follow the specification.
How to fix it
Set /Subtype /text#2Fxml on the embedded file stream.
Related rules
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