【PS4: General】How to Re-download Previously Downloaded Content
Content that has been downloaded from the PlayStation Store can be re-downloaded at no additional cost by logging in with the same Sony Entertainment Network account used for the original purchase.
【How to Re-download】
1.From the home screen, select [Library]
2.Choose [Purchased]
3.Find the game and locate it, and then go to [PlayStation Store] > [Your Add-Ons]
To begin downloading, locate the content you wish to download and click the download icon (arrow) next to it.
If the content is already installed, the description in the [Your Add-Ons] screen will show [Installed], and re-downloading is not necessary.
For more details about downloadable content, please visit Here.
(You will be redirected to the relevant section of the official Sony Interactive Entertainment website.)