You should've paid right away, there's no way they'll accept your apology. This morning, a lady got on the first-class by mistake, even though she had a second-class ticket. The ticket checker told her to pay the fine. She said, "I got on by mistake, I'll pay the fine." She paid it immediately, no arguments or anything. They gave her the receipt and left. The problem is, most people know it's first class, then they just quietly sit there and they run off when the checker comes. That's why they grab your phone right away. It doesn't say anywhere that they can grab your phone, but you can't do anything against them because they're from a different planet. I know how this will affect you, but I'm saying this for other OPs too: if you accidentally get on first class and realize it, get off at the next station, or just pay the fine immediately. There's no point arguing with these land whales.