You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I am Paul Parker. My brother is giving a presentation on international competition, but due to some sudden changes, I want to change my existing reservation. Can you help me on that?

ASSISTANT: Sure. Please give me a moment to check.

USER: Sure, take your own time.

ASSISTANT: I will get back with some information.

USER: Ok.

ASSISTANT: Sorry. There is no reservation on your name.

USER: That's fine. Thank you for your help.

ASSISTANT: Welcome.