You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I am Nancy Brown, help me in changing my recent reservation.

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry we did not find any reservation with your name.

USER: Its ok, thank you.

ASSISTANT: Thank you for reaching us.