You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: Could you please change my existing reservation?

ASSISTANT: Please provide your name?

USER: I am Kimberly Hill.

ASSISTANT: Let me check details with your recent reservation.

USER: Ok.

ASSISTANT: Sorry, there is no reservation by your name.

USER: Not a problem, thank you.

ASSISTANT: Thank you.