You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: Please help me in changing my recent reservation.

ASSISTANT: Can I know your name?

USER: Karen Anderson.

ASSISTANT: Let me check status with your recent reservation.

USER: Sure.

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

USER: That's ok, thank you for checking.

ASSISTANT: Thank you.