Mystery Apple bill charge on my bank statement

Settings, tap your name at the top, Media and Purchases, View Account, Purchase History. Every charge is listed with the exact app or item. The apple bill label often lumps a few small purchases into one charge a few days later, so match the total rather than the date. Also look at Settings, your name, Subscriptions, because a free trial that quietly converted is the usual answer. If you're in a Family Sharing group as the organiser, someone else's purchase lands on your card and shows up in that same history. If it's genuinely not yours there's a Report a Problem option against each item and refunds for an unrecognised small charge usually go through.