You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you at this moment?

USER: Is this Central travel agency? Yesterday I booked a ticket to New York through your agency, your agent  by mistakenly booked a ticket  on wrong dates, so I want to change my reservation.

ASSISTANT: Ok, sure I can search with your ticket reservation.Can I know your name?

USER: I booked a ticket on the name of Margaret Lee.

ASSISTANT: Sorry for the inconvenience, no reservation found on your name in my database.

USER: That's fine, I will try for other agency.

ASSISTANT: Thank you for reaching us.

USER: You are welcome.