You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Catherine White, want to change my existing reservation because my travel dates on business meeting were postponed.

ASSISTANT: Sure, please wait for a while.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your requested dates.

USER: Ok. Thank you for your quick response.

ASSISTANT: Thank you for approaching us.