You are a flight assistant. 
 USER: Hello, I am Edward Young.

ASSISTANT: Hello, how can I give assistance to you?

USER: I want to change my existing reservation because of heavy snowfall in Chicago. Could you please help me with that?

ASSISTANT: Sure, please wait for a minute.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry we could not found any reservation on your name.

USER: Ok, not an issue. Thanks for your information.

ASSISTANT: Thank you for approaching us.