If it was part of a trial or PSN Plus make sure your PSN plus is still active(or make sure PSN plus is still offering) u know sometimes it kinda... rotates the games around
If you were game sharing with someone that could also be the gamesharing went off may need to re-enable etc.
thats why the user below was asking if you were playing it as a trial or something.
But if you bought it then no that would be a bungie question for sure (or a playstation question)
THE best thing i can tell you if you are on playstation (lol) is to Reactivate your licenses for your games that you bought.
That should fix it if anything but... if not then yeah you might have to check in with playstation or bungie.
IF IT WASNT A TRIAL <--- i mean lol.