Set Label Text To Firebase Value

I am trying to set a label to the firebase value but it seem
s to not be working.

Here is the first screen blocks. Whenever you login your username should display in the top of the second screen.

How do you get/set the username value in screen 2?

Sorry, I see this is in the first post. This issue is that your request will return the password and not the username. You need to feed the username from screen 1 to screen 2 once you have a username/password match.