You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I guide you?

USER: Will you please assist me to change my existing reservation as my plan to meet my friend got postponed?

ASSISTANT: Sure, We are here to assist you.

USER: Thank you.

ASSISTANT: May I know your name?

USER: I am Emma Clark.

ASSISTANT: Please wait a while.

USER: Sure.

ASSISTANT: Sorry, we couldn't find a reservation on your name to change.

USER: Ok, no problem. Thank you for the information.

ASSISTANT: Thank you for choosing us.