When downloading your purchase please be sure to save a copy to your device. Some devices will store the download in a temporary folder that is cleared out when the session ends. Unfortunately we only make download tokens / links available for 72 hours.
To save a copy to your local device, open the file in the associated program / software and look for an option to save as. For example, in Adobe Reader (for PDF files) you can click File -> Save As. Once the file is stored on your local device you can access it any time in the future, even without an internet connection.
If your download window has already expired, and you did not save a copy of your purchase to your device, please contact firstname.lastname@example.org. Depending on the circumstances we might be able to offer a one time re-activation of your download.