You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: My name is Kenneth Lewis.

ASSISTANT: How can I help you?

USER: As my trip got postponed, I would like to change my reservation.

ASSISTANT: Give me a minute, let me check the details.

USER: Ok.

ASSISTANT: Sorry, there are no reservations found on your name.

USER: That's fine. Thank you for your time.

ASSISTANT: Welcome.