With the launch of New Light, changes were made to the progression system, and the legacy campaigns as well. Any campaigns that had not been completed prior to the update, had their progress reset. That means that you would need to start over from the beginning, if you wish to play those campaigns. Amanda in the Tower Hangar will have the legacy campaign quests for the year one stories. If you own Forsaken; you can start that campaign by opening your director, going to the Tangled Shore map, and selecting the Last Call mission icon towards the bottom of the map.