The person you're talking to got swapped. You don't notice.
In 1998 Simons and Levin had a stranger ask pedestrians for directions. Two workers carried a door between them and the asker was swapped for a different person. Only 7 of 15 pedestrians noticed. You don't store a picture of a scene, just a few relevant features.
Useful: Eyewitness descriptions of appearance are far less reliable than they feel.
Source: link.springer.com