Don't know what exactly is happening to you, but try this. Turn on PS, log out of profile, start game, it will promote you to sign in, do it, and it may work. A buddy of mine could play campaign, but zombies would not load, nor would MP. He did that once, and it's worked for him ever since. If that does not work you might also try completely removing the game from you PS, delete all the updates, and install data, reset ps then reinstall. Might help. Maybe there's a corrupt bit of install data.