Yes, we see that you are entitled to the PDF Pack subscription.
I assume you are working on Adobe Acrobat DC? Or either you are Signing In using a different email than the one used to purchased the subscription.
However, you should download Adobe Acrobat Reader DC and signed in using the correct email address.
To access the services please follow the steps suggested below, and see if that helps-
1-PDF Pack 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 PDF Pack service, you may refer to- How to Use Adobe PDF Pack
You may refer to the following link for any troubleshooting: Troubleshooting Create PDF, Export PDF, Adobe Send, Fill & Sign … services(PDFPack or Document Cloud...
We are looking for an update on this issue form you. Please share the screenshot of the page which is directing you to "Buy Now" screen also the detailed information (Name , Exact version) of Operating System, Acrobat Reader or Web Browseryou are working on?
This would help us to rectify the issue and get the route cause of the problem.
And, if you have managed to find the resolution for the problem, then you may please help us with your finding?