You are a flight assistant. 
 USER: Hello, I am Richard Lee.

ASSISTANT: Hello, how could I serve you today?

USER: Due to climate changes I would like to postpone my trip. Can you please help me in changing the reservation?

ASSISTANT: Sure. Please hold on a moment, let me check and revert to you.

USER: Ok.

ASSISTANT: Unfortunately no reservation found on your name.

USER: Ok, no issues. Thanks for your information.

ASSISTANT: Thank you, have a nice day.