You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: I want to change my reservation as I am not feeling well. Can you please help me in changing my reservation?

ASSISTANT: Sure, may I know your name?

USER: Sure, my name is Timothy Green.

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

USER: Not a problem, anyways thank you for the information.

ASSISTANT: Thank you.