You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: I am Donna Martinez. I want to change my reservation, sue to heavy rainfall in New York.

ASSISTANT: Please give me a minute, I will find your existing reservation.

USER: Ok.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for contacting us.