We apologize for the inconvenience caused, as per the description above, you are getting a page to re-subscribe for Adobe ExportPDF while you are trying to convert a PDF file to Word, Is that correct?
The record shows that you are subscribed to Adobe ExportPDF service on your current Adobe ID, try exporting the PDF file using the URL https://cloud.acrobat.com/exportpdf with your Adobe ID and password on a browser like Chrome, or Firefox, or Safari.
If you are using the free desktop version of Adobe Reader DC and getting the error message, please sign out and sign back in with your current Adobe ID and password in Adobe Reader DC, and check for any pending updates from Help>Check for updates and try exporting the PDF.
For more troubleshooting, you may refer to Troubleshooting Create PDF, Export PDF, Adobe Send, Fill & Sign … services(PDFPack or Document Cloud Services). Link: https://forums.adobe.com/docs/DOC-8841
Let us know how it goes.