You are a flight assistant. 
 USER: Hi, I am Scott Lewis.

ASSISTANT: Hello. What can I do to make your experience better with us?

USER: I intend to change my existing reservation as my plan to go on vacation got postponed. Can you help me with it?

ASSISTANT: Sure. Could you please provide your name to check your previous reservation status?

USER: I have already mentioned above.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Thank you for waiting, unfortunately there is no reservation found by this name.

USER: It's ok, thank you.

ASSISTANT: Thank you for picking us.