https://www.playstation.com/en-us/explore/ps4/

Learn what steps you can take if a PS4 game is marked with a padlock icon and cannot be played. First you'll see how to confirm ownership of digital PS4 games. Next you'll learn how to restore licenses for digital PS4 games. Instructions for deleting and re-downloading games are included in case license restoration doesn't solve the issue.
Check out these videos to learn more about PS4 downloads.

To learn about PS4 Downloads, visit https://youtu.be/ZdJ6pir9lGc
To learn about Pre-Ordering PS4 Games, visit https://youtu.be/Rh6sm02yCX4
To learn about PS4 Automatic Downloads, visit https://youtu.be/MoRhQDFCR9E

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