Additional fee to use acrobat.com if I'm a Creative Cloud subscriber?

I'm a Creative Cloud subscriber, and I was trying to use the 'Send for Shared Review' feature in Acrobat, but I can't upload any files when I sign in using my Creative Cloud account info. I'm not getting any errors, just this dialog box when I get to the in upload phase.

At this point nothing happens. I can Cancel or Retry, but retrying just brings up the same dialog that never progresses.

Should I be able to use this feature, or is the use of acrobat.com not included in my Creative Cloud subscription?

Thank you for any help you can provide.