During the scene when Erin and her boss go back into his office while meeting with another lawyer, Erins boss pulls off his tie. The camera changes the shot and points to Erin. When they go back to the boss, his tie is now tied. The camera again goes back to Erin and then back to the boss. This time, the tie is untied.
You are correct but its a minor slip. Ed Masry does begin to tug at his tie when they cut to Erin. When the return to Ed, a split second later, the tie is neatly tied up to the neck. I'd rate this slip up very low and very minor.