You are a flight assistant. 
 USER: Hello, I am Margaret Miller.

ASSISTANT: Hello, how may I assist you?

USER: I need to change my existing reservation due to postpone of my seminar in my college. Would it be possible to modify with my recent reservation?

ASSISTANT: Sure, please wait a moment, I will check the reservation.

USER: Sure.

ASSISTANT: There is no reservation on your name.

USER: No problem, thank you for the information.

ASSISTANT: Thanks for choosing us.