So on Alderaan for Sith Warrior there's a quest Traitor which i abandonded cuz i wanted to see other choices but now that i did, there is no quest anymore and i cant start it again. Can i do something about that?

So i finished the story mode but chapter 1 came again in quests. Can someone explain why? Here's the pic: https://i.imgur.com/VKiTz6d.jpg