Lost YSL Cardholder Tuesday, 9/9 on 39 Bus traveling Back Bay Station (Boston)

I lost my YSL Black Card Holder in Prada nylon pouch on Tuesday, 9/9 on 39 Bus traveling Back Bay Station. I was on the bus that departed Back Bay at 4:11 PM (I believe). I offered my seat to an elderly man and I'm not sure if the PRADA pouch fell out out of my bag with my YSL Cardholder in it or if it fell in the seat and the older gentleman sat on it. I have my work MBTA Commuter card, my debit card, credit cards etc. Would really appreciate it's return :( Thank you, Jen