I sign in and click on the converter button and it tells me I have to pay. I clicked on that to see what would happen and then it tells me I already have a subscription. How do I actually get to use the converter without this circular problem?
Please try to sign out and relaunch the application.
Then sign in with your Adobe ID and check if you can export the application.
In meantime, you can export PDF online here: https://cloud.acrobat.com/
Let us know if you experience any issue.