Part 4 of the mission that says “Help Superman defend star labs research base” where you have to locate super man and then help him fight lex Luther keeps glitching out right when lex Luther shows up and then nothing happens. I can still move around and do things but lex Luther and Superman just sits there and the game doesn’t progress. I cannot progress in the game unless I do this mission so I’m just stuck not being able to play.

I reached out to daybreak and below is the steps they told me to take. I tried all steps in order and it still didn’t work.
Instructions sent by daybreak
For the “Help Superman defend Star Labs research base” step, this may happen when the mission scripting does not advance properly after Lex Luthor appears. Please try restarting the mission/instance and progressing through it slowly. Make sure to defeat every enemy in each area before moving forward, avoid rushing or flying ahead, and allow all dialogue to finish before entering the next room.
If Superman and Lex Luthor remain stuck, please also try the following:
1. Step back out through the doors you used to enter the boss room, wait around 30–60 seconds, then walk back in.
2. Open your Map, select the Warp Menu, and use Warp to Rally to reset your position inside the instance.
3. Open your Journal, select the mission, check the Rewards tab, and press your action/accept button to see if the objective updates.