Something to try - Review the service's FAQs and related information articles.
The service has some specific prerequisites that must be met.
So, as a subscriber, you'll want to be sure you have "read the manual".
Some subscriber resource that you do need to make use of.
You can get into live chat via the first link below.
https://new.acrobat.com/en_us/support/export-pdf.html
http://forums.adobe.com/community/exportpdf
http://helpx.adobe.com/contact.html
Be well...
("RTM" - always a good thing)