You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Jonathan Baker.

ASSISTANT: How can I help you Jonathan Baker?

USER: Due to heavy rainfall in New York, I want to change my existing reservation.

ASSISTANT: Sure, give me a minute, let me check the reservation status in our database.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found with your name to change it.

USER: It's ok, thanks for helping me out.

ASSISTANT: Thank you, have a great day.