Learn how to activate your game on playstation-store
1.Login to your PSN account or create a new one. Make sure to use the correct country. You can create the account from your PS4 or online.
2.Select the Playstation Store icon from the main menu.
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3.On the Playstation Store, under the menu, select Redeem a code.
4.Enter your code.
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5.Once the code entered, select continue.
6.If you wish to start right away the download of the content, just select Download.