@skewgyy Oh! I got confused. I thought you were buying it for PS4. :-/ Anyway, I did a bit more research. There are a number of reports from folks having trouble with launching the game and/or not seeing their purchased content.
Since it shows the content is owned in your My Kits, I wonder if you just need to download it. In the EA app, search for the Grunge Revival kit. When you click on it, do you see a "download" option? I don't have this kit so my only option is "purchase". If you do have the option, then click to download and, when it's done, launch the game to check if the content is there.
If that doesn't work, perhaps you could try getting the Base Game from Epic and launching the game using their launcher. There are some reports that doing this will add Epic content to the EA app library. As long as you have the EA app, that should open as well. Check to see if the content is available. If it's not there, close the game and search for the kit in the EA app again to see if you get a "download" option.
Please come back and update if any of this works or not, or if you need more help.