You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I best assist you today?

USER: Owing to an emergency I need to change my existing reservation. Can you please help me out?

ASSISTANT: Sure, may I know your good name please?

USER: My name is Susan Hernandez.

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: Thanks for waiting, no reservation found with your name to change.

USER: OK, no problem. Thanks for your information.

ASSISTANT: Thanks for opting us, have a nice day.