You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you now?

USER: I am Katherine Scott here. I would like to change my existing reservation, which is done recently. Can you please help me out?

ASSISTANT: Sure, I will help you with that.

USER: Thank you for considering my request.

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

USER: Sure, I will wait for your response.

ASSISTANT: Sorry Katherine Scott, no reservation has found under your name to change.

USER: Not a big problem, anyway thank you for the information.

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

USER: Thank you for searching.