You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

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

ASSISTANT: Sure, please provide your name to check your reservation.

USER: Sure, my name is Shirley Jones.

ASSISTANT: Please wait a moment, let me check.

USER: Sure, take your time.

ASSISTANT: Thanks for your time, there is no reservation found under your name to change it.

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

ASSISTANT: Thanks for choosing us.