You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I aid you?

USER: I want to change my reservation due to sudden change of my plan. Can you help me with that?

ASSISTANT: Sure. May I know your name?

USER: My name is Brian Wilson.

ASSISTANT: Please wait a moment.

USER: Ok.

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

USER: No problem, thank you for your valuable information.

ASSISTANT: Thank you for opting us.