PSN sign-in bug: Try logging out of your PSN account completely, then sign back in and launch Destiny again. Bungie-side issue: Sometimes Destiny has trouble verifying PSN sessions even when PSN is up. You can check BungieHelp on Twitter or Downdetector to see if others are having login problems too. If it’s only affecting Destiny and not other games, it’s probably on Bungie’s side, and waiting it out or retrying in a bit usually works.