You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you at this moment?

USER: I am Gary Hill, I need to modify my reservation as my schedule got postponed. Can you please help me out?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Please wait a moment to check your reservation status.

USER: Sure, have your time.

ASSISTANT: Sorry Gary Hill, no reservation has found under your name to change.

USER: It's ok, anyway thank you for the information.

ASSISTANT: Thank you for choosing us, have a good day.