Reinstall games who deleted library?

My cousin had bought GTA 5 on playstation store, deleted it and deleted it from the library. Now he wants to play this game again but doesn't know how to install it. He can no longer install it on Ps-store and neither can the library. Can you do something about it?

You can't delete PS4 games from the library.

But somehow he did it, I also thought that you can't delete them from there

No, this is simply not possible. Sony has never added such a feature. Have a look at the library under games bought or something like that

Thank you, my cousin found the game again and was able to install it, thanks again