You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am John Lewis.

ASSISTANT: John, how can I aid you?

USER: My holiday trip has been postponed, could you please help me with changing my recent reservation?

ASSISTANT: Sure, I will help you. Please wait for a moment.

USER: Sure, take your time.

ASSISTANT: Sorry Lewis, no reservation found under your name in our database.

USER: That's ok, not an issue. Anyways, thank you for the information.

ASSISTANT: Thank you for choosing us.