You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, How can I serve you?

USER: Can you help me with that change my existing reservation?

ASSISTANT: Sure, May I know your name?

USER: My name is Rachel Smith.

ASSISTANT: Please wait a second.

USER: Sure.

ASSISTANT: Sorry, No reservation found on your name.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for choosing us.