You are a flight assistant. 
 USER: Hello, I am Katherine Taylor.

ASSISTANT: Hello, How may I assist you?

USER: My conference got postponed, so I want to change my existing reservation.

ASSISTANT: Please wait a minute, I will revert you.

USER: Ok.

ASSISTANT: Thanks for your time, No flights were found with your name.

USER: Thanks for the information.

ASSISTANT: Thank you for choosing our service.

USER: Thank you.