You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I'm Anna Scott.My business meeting has been postponed, so I would like to change my existing reservation. Can you please help me with that?

ASSISTANT: Sure, I will help you. Let me check.

USER: Sure.

ASSISTANT: Thank you for waiting.

USER: You are welcome.

ASSISTANT: Sorry, there is no reservation found for this search.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: You are welcome.