You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am Lisa Wilson. Can you help me in changing my reservation?

ASSISTANT: Sure, I can help you with that. Please wait a moment I will check your details and get back to you.

USER: Sure.

ASSISTANT: Sorry to say, I did not find any reservation on your name.

USER: That's fine. Thank you for your immediate response.

ASSISTANT: Thank you for choosing us, have a nice day.

USER: You are welcome.