Update: I eventually found that the documents are stored on something called "Document Cloud" (documentcloud.adobe.com). In order to do this, I signed another document (this time a blank page with no sensitive information) and created that link just like last time. It is only by following that link that I discovered the existence of this "Document Cloud". This shouldn't have been so convoluted. It's like Adobe is trying to hide your own documents from you!
However, while my documents were indeed listed there, there was no option to delete. I eventually got in touch with a very helpful support staff person who guided me through the process for deleting signed docs (called "agreements"). For those looking to do the same, here goes:
- open Document Cloud in your browser and sign in
- click on your profile picture in the top right corner and click on "Settings", and then on "edit settings"
NOTE: I got a "server error" message here while using Chrome. It worked for me with Edge. I don't know about other browsers.
- on the edit settings screen, go to "Privacy" on the left-hand menu
- then you have to search for the document by typing in an e-mail address that it's associated with. If you created the document, just use your own address (the one that's associated with your Adobe account)
- now you will see the document list. Each document has a little trash/bin icon associated with it. Click on the trash/bin icon. Congratulations, you have submitted a "request" to delete the document.
Hopefully, I will get a confirmation e-mail to say that the documents have indeed been deleted.
In conclusion, this was far too much trouble just because I clicked on "Next" after signing a document. Accessing and deleting your own data should not be this buried and complicated to figure out.