You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How Can I help you today?

USER: I would like to change my existing reservation, Can you help me with that?

ASSISTANT: Sure, May I know your name please?

USER: My name is Virginia Phillips.

ASSISTANT: Ok, please wait for a minute.

USER: Ok.

ASSISTANT: Sorry, there is no reservation with your name.

USER: Ok, Thanks for your information.

ASSISTANT: Have a Great day.

USER: Thank you.