When you meet Ellie for the first time and is running super speed at the same time, the dialog gets bugged.
When you approach her and there is a bit of dialog, it skips through sort off. The main point is that the elevator door gets stuck in 'Standby' mode and doesn't get unlocked meaning you're stuck.
Easily fixed by deactivating the super speed option in the trainer, however you have to do it before the dialog starts! Otherwise you're stuck, provided this glitch happens to you.