Hi Jeromeb,
To access the Export pdf subscription, you may follow the instructions given below-
1- Export PDF is an online service that you can use online via: https://cloud.acrobat.com/exportpdf
2- You can also use the services through free desktop version of Adobe Acrobat Reader DC: Adobe Acrobat Reader DC Install for all versions
3- “Sign In” using the email (Adobe ID) under which you have subscription registered.
4- For detailed description of how to use the Export PDF service, you may refer to- Using Adobe Export PDF
I assume you are working on Adobe Acrobat DC? However, you should download Adobe Acrobat Reader DC and signed in using the correct email address.
You may refer to the following link for any troubleshooting: Troubleshooting Create PDF, Export PDF, Adobe Send, Fill & Sign … services(PDFPack or Document Cloud Services).
Let us know if it still doesn't work.
Regards,
Akanchha