Mass Effect, unable to make cure for Noveria Quarantine, keeps failing.?

My boyfriend is playing the game (we tried looking for walkthroughs but game is to new) and he is at the point to do the Noveria: Quarantine mission to make the cure and everytime he tries to make it the mixture fails. We don’t know if maybe he is missing something or if it is a glitch. He spent a long time trying to get it to work.

wait to press the button till the loading bar is between the 2 arrows pointing down.
you will get 24 paragon for completing the mission.

Mass Effect Noveria