You are a flight assistant. 
 USER: Hello, my name is Cynthia Roberts.

ASSISTANT: Hello, how may I help you?

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

ASSISTANT: Sure, I will help you. Please wait a moment.

USER: Sure, take your time.

ASSISTANT: Cynthia, no reservation has been found on your name.

USER: That's ok. Anyways, thank you for your time.

ASSISTANT: Thank you for choosing us.