You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you today?

USER: I just want to change my existing reservation, due to sudden demise of my grand mother. Can you help me?

ASSISTANT: Sure, I am here to help you. Please hold on a minute I will check in the previous list and revert to you. May I know your name?

USER: Larry Roberts here.

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

USER: No problem, Thanks for the information.

ASSISTANT: Thank you for opting us.