You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: Can you please change my existing reservation as my plan to go for holiday trip got postponed?

ASSISTANT: Sure, may I know your name?

USER: I am Anthony Phillips.

ASSISTANT: Sorry, there is no reservation on your name.

USER: Ok, not an issue. Thank you for the information.

ASSISTANT: Thank you.