Hi, I merged your post with your previous Black Mirror 3 thread.
This part of the game has been buggy for quite a few people, and this may be the problem in your case as well. I found this from the Steam forum for the game:
I found out this part of the game is indeed bugged. The game doesn't properly recognize the solution of the underlining in the journal. You have to keep it open without underlining and after a while the skip button/lever will appear at the bottom right corner, click it and then you can progress the game.
Is there a way that you can load a save game prior to the underlining so that you are able to skip the puzzle by following the instructions above? That might get you moving again.