You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you for today?

USER: My name is Paul Mitchell. I would like to change my existing reservation to some other dates. Can you help me?

ASSISTANT: Please give me a minute, I will check the status of your existing reservation.

USER: Ok, take your time.

ASSISTANT: Sorry, there is no reservation found under your name.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for contacting us, have a nice day.