You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I want to change my existing reservation, as my health is not good to travel. Can you please help me?

ASSISTANT: Sure, I can help you with that. May I know your name for checking your previous reservation status?

USER: I am Scott Walker.

ASSISTANT: Ok, please hold on a moment, I will check flight availability.

USER: Sure.

ASSISTANT: There is no previous reservation available on your name Scott Walker.

USER: Ok, no problem. Thank you for your information.

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