You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am James Evans.

ASSISTANT: How can I assist you today?

USER: Will you please be my helping hand in changing reservation as the presentation which I want to give in my college got postponed?

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: There is no reservation found on name of James Evans.

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

ASSISTANT: Thank you for approaching us, have a nice day.