You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Sure, I am here to help you out. May I know your name please?

USER: Myself Eric Baker.

ASSISTANT: Eric Baker, we haven't found any reservation under your name in our database.

USER: Not an issue. Thank you.

ASSISTANT: Thank you for choosing us.