You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you now?

USER: Due to an emergency, I would like to postpone my journey. Please change my existing reservation.

ASSISTANT: Sure, I will change your reservation. May I know your name please?

USER: My name is Rebecca Rodriguez.

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

USER: Its ok, thank you for the information.

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