Hi Risleym,
We have checked your account information, and found an active subscription of Export PDF.
As you have also confirmed that you are able to access the service online via- https://cloud.acrobat.com/ this means that nothing wrong with the subscription activation.
I assume that you have been trying to access your Export PDF subscription through wrong application Adobe Acrobat DC not Reader DC?
Please ensure that you are working with Adobe Reader DC not Acrobat DC to access PDF Pack and "Signed In" using correct email.
You can download the Reader DC through- Adobe Acrobat Reader DC Install for all versions
For further troubleshooting you may refer- https://forums.adobe.com/docs/DOC-8841
Let us know if this doesn't help.
Regards,
Akanchha