You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I guide you at this moment?

USER: I would like to change my planned dates to some other dates, please help me in changing my existing reservation.

ASSISTANT: Sure, I can help you in that.

USER: Thank you.

ASSISTANT: May I know your good name please?

USER: My name is Dorothy Phillips.

ASSISTANT: Ok, please wait for a while.

USER: Sure, take your time.

ASSISTANT: We are sorry to say that, there is no active reservation found on your name.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thanks for connecting with us.