Did you make sure to set your PS4 as your primary console? Can you try deleting the game install, signing out of your console, rebooting the console, sign back in and set your console as your primary console. Before reinstalling the game, try accessing the DLC either in the addons list of the game or remotely push the downloads from your PC. To remotely access the content please see the link from Sony: Issues downloading content from the Library. If you are trying to access the content from your console, the add on's section may appear empty or asking you to repurchase the content, if you select "View All" you should be able to access your content. Hopefully that helps, keep us posted on your results!