You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I aid you?

USER: Can you help me to change my recent reservation as my travelling dates are postponed?

ASSISTANT: may I know your trip dates? I am sorry, may I know your name?

USER: Sure, I am Stephen Smith.

ASSISTANT: Sorry, no reservation found on your name.

USER: Ok, not an issue. Thank you for searching.

ASSISTANT: Thank you.