So idk if I'm the only person this is happening to, but I bought Forsaken on sale a bit before Shadowkeep. Haven't gotten around to finishing Forsaken until recently because of college. Its been a week since i've finished it, but I tried to run the shattered throne this morning and it said I didn't own the campaign....? I HAVE the Ace of Spades. I literally would not have this gun without completing the campaign. I'm already trying to buy shadow keep first chance I get, but come on, I gotta buy forsaken again?? Am I the only one who's dealing with this?? plz help im too broke to buy two campaigns. Maybe im just stupid or this has something to do with PS4. IMPORTANT EDIT: I forgot to mention this happened AFTER the latest update (jan 28 2020) where inventories got erased. My hunch is that maybe it has to do with that
If the game indicates you don't own Forsaken then you'll need to contact Playstation support as they would be responsible for what licenses are active on your account.