You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how best I can aid you today?

USER: I want to change my reservation due to sudden health issue, can you please change my reservation?

ASSISTANT: Sure, we are glad to help you to change it.

USER: Thank you.

ASSISTANT: May I know your name?

USER: Sure, my name is Jonathan Carter.

ASSISTANT: Thanks for providing your name, please wait for a while.

USER: Sure, take your time.

ASSISTANT: Thanks for your time, there was no reservation found on your name to change it.

USER: Oh! I think the ticket was not booked due to server issue. Anyway, thank you for the information.

ASSISTANT: Thank you for approaching us.