I was on a subway station. I charged my card and went through the turnstile, but then a girl from my class appeared and I went up to her, passing underneath the turnstile. The machine had given me some weird coins and one of them looked like a debit card, and I asked my colleague if she knew what it was. I then passed over the turnstile to get to the other side again and some woman who worked there told made me go with her into a room which looked like an office and showed a screen where you could see the part of the turnstile and the machine. I told her why I did it and she told me she'd seen it but that I had to stay there anyway (?).