We need additional information to troubleshoot the error.
  – Are you able to EXPORT the PDF from the plugin’s EXPORT tab?
    –  If yes, there is an issue with the Shortcode – please upload a screenshot of the Field Map Layout and the PRO2PDF Shortcode in the Formidable Form’s On-Submit Message Box.
    –  If no, was the PDF form created in Adobe Acrobat or another PDF form editor?
       Please upload the PRO2PDF template to this form. (WP DASHBOARD → FORMIDABLE PRO2PDF → TEMPLATES → EXPORT)
Or complete this form to have us log in to see the issue.