You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: Our friend have planned a trip and suddenly the trip got cancelled and changed to other dates, can you please modify my ticket booking?

ASSISTANT: Sure, I can help you with that.

USER: Thank you.

ASSISTANT: May I know your name for checking your previous reservation status?

USER: I am Angela Taylor.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: There is no previous reservation available on your name Angela Taylor.

USER: That's fine, no problem with that one. Thanks for your service.

ASSISTANT: Thank you for reaching us.

USER: Welcome.