You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I assist you?

USER: Please help me in changing my recent reservation.

ASSISTANT: Sure, I am here to help you out.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Matthew Thompson here.

ASSISTANT: Wait a moment please.

USER: Sure.

ASSISTANT: Matthew Thompson, we haven't found any reservation under your name in our database.

USER: That's ok, thank you for your information.

ASSISTANT: Thank you for choosing us.