The other comment gave me the answer, I was just dumb and didn't understand I could select the other line of dialog. When you talk to the ticket office, I thought that the second line of your character's dialog (the one a little bit grayed out) was her "internal thought", just something that the character is thinking, and you have to find a clue somewhere so they understand that it's the right choice and will choose it by themselves. I didn't notice the arrow on the left, I didn't understand I could choose between the two lines.