You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

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

ASSISTANT: Sure, may I know your name?

USER: My name is Laura Mitchell.

ASSISTANT: Sorry, there is no active reservation on your name.

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

ASSISTANT: Thank you.