You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How exactly I can serve you the best today?

USER: My board meeting has been postponed, I want to change my existing reservation. Can you please change my reservation?

ASSISTANT: Sure, I will help you with that. Let me know your name to check your reservation?

USER: Sure, I am Susan Campbell.

ASSISTANT: Please wait a moment.

USER: Ok.

ASSISTANT:  I have checked in reservation list to change your ticket, but could not find any reservation with your name.

USER: Ok, Thank you for your service.

ASSISTANT: Thank you for choosing us.