You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I assist you?

USER: I am Sarah Taylor. Can you please assist me in changing my existing reservation as my plan to meet my friend got postponed?

ASSISTANT: Sure, please wait a moment.

USER: Sure.

ASSISTANT: Sorry, there is no reservation found on your name.

USER: It's ok, no problem.

ASSISTANT: Thank you for approaching us.

USER: Thank you for the information.