Lost Items

A few minutes ago, I saw a visually impaired man who was supported by a station worker to get on the train. That train wasn’t going to my station, so I stayed at the platform. Just as those people got on the train, I noticed that something fall between the train and platform. The train left immediately, and then the train which I needed arrived. As I was getting on, I looked at the gap and saw something that looked like a card. I told a station worker about it and I felt regret that I could have done something before the train with the blind man left.