What would you say or how would you feel about a gender mix-up?

If you were walking across a large plaza and seen two people sitting with their backs to you in jackets that seem similar, jeans, one in sneakers the other in Jackboots. One has very cropped hair, the other people has hair to their mid back and appears of similar size and build to the other. You don’t see any faces but they rise to leave as you approach the bench. You noticed one with long hair has lost their cell phone from their pocket. You retrieve the phone and dash up to that person and say ”Ms. You lost your phone from your pocket”, only to have them turn and the one with the cropped hair and Jackboots was the female and the one in sneakers and long hair was the male. What would you say other than ”oops”?