You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Patricia Young.

ASSISTANT: How can I serve my best for you at this day?

USER: I want to change my reservation, can you please help me?

ASSISTANT: Ok, please wait for a while. I will check and let you know about your reservation status.

USER: Sure.

ASSISTANT: Sorry, no reservation found on your name to change.

USER: Ok, not a problem. Thank you.

ASSISTANT: Thank you for reaching us.