You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Sharon Walker.

ASSISTANT: Good evening, how can I aid you?

USER: I want to change my reservation because my exam was postponed so help in changing my reservation?

ASSISTANT: I can help in that changing, wait a moment to check your booking. Sorry Walker, no reservation found for this search on your name to change your booking.

USER: Oh might be my brother has changed, that's fine. Thank you for your help.

ASSISTANT: You are most welcome.