You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: My business meeting has been postponed.Can you please help me for changing the existing reservation?

ASSISTANT: Sure, may I know your name?

USER: My name is Andrew Hernandez.

ASSISTANT: Sorry, no reservation found Andrew.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your service.