You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I made a reservation earlier this week to give a seminar, but my seminar has been postponed. Can you please change my existing reservation?

ASSISTANT: Sure. may I know your name please?

USER: My name is Shirley Perez.

ASSISTANT: I am sorry no reservation found on your name.

USER: No problem, thank you for your information.

ASSISTANT: Thank you for choosing us.