You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: Could you please change my existing reservation?

ASSISTANT: Sure, I am here to help you. Can I have your good name?

USER: I am Jack Smith.

ASSISTANT: Sorry, there is no active reservation on your name in our data.

USER: No problem, thank you.

ASSISTANT: Thank you for choosing us.