Why can't I permanently delete files from acrobat.com?

I'm uncertain if what I'm experiencing is the same as all above. It's along the same lines. I recently opened the online acrobat.com files account and need to delete a pdf file from the list online. I read above about the 2 part step with archiving then deleting. However, I can't seem to locate any info on my screen on how to archive in order to delete the file from online. Please help!