You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I am Elizabeth Robinson. Owing to an emergency, I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Ok, can you please wait a minute?

USER: Sure.

ASSISTANT: Thanks for your time. Sorry, there was no reservation on your name in our data base.

USER: Not an issue. Thank you.

ASSISTANT: Thank you for availing us, hope we serve you next time.