You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you at this moment?

USER: Can you please help me in changing my existing reservation?

ASSISTANT: Sure, I will help you with that. Can you please provide your name to check your previous reservation?

USER: My reservation was done in the name Shirley Turner.

ASSISTANT: Ok, please be on hold.

USER: Ok.

ASSISTANT: Sorry to inform you that, there is no reservation found with your name in our records.

USER: Ok, fine. Thank you for informing me about my reservation.

ASSISTANT: Thank you for approaching us, have a great day.