You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: I am Katherine Lee. Can you please change my existing reservation which I have done earlier?

ASSISTANT: Sure, I am glad to help you with that. Please give me a moment to check your reservation status.

USER: Sure, take your own time.

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

USER: Ok, no problem. Anyways, thanks for the help.

ASSISTANT: Thank you for reaching us.