The PDF downloads are set for 3 accesses, and each time you open the file (regardless of if you save it) counts as one. Therefore, be prepared to SAVE the file in a safe place once you open it. This is so that you ALWAYS have access to the product you purchased!
The first page of the pattern tells you this, too, and you can delete that first page from the PDF once you have it saved in your library. It’s not possible for me to test every combination of tablet, phone, or computer and software to make sure they all work, so please take a few minutes to learn how your computer or device saves files before purchasing PDFs.