You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Due to some entrepreneurship meeting, I am going to change my existing reservation. Can you please help me in changing the reservation?

ASSISTANT: May I know your name to check with booking status?

USER: Sure, myself Christine Miller.

ASSISTANT: Ok, please allow me to check with booking.

USER: Sure, take your own time.

ASSISTANT: Sorry to say, there is no flight reservation available by your name.

USER: That's ok, no problem.

ASSISTANT: Thank you for choosing us.

USER: Thank you for the information.