You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I have already reserved my ticket, but right now I want to change my reservation.

ASSISTANT: OK, may I know your name please?

USER: Could you please help me with change reservation? My name is Carol Martin.

ASSISTANT: OK. Just give me a minute to check.

USER: Sure.

ASSISTANT: Sorry Martin, unfortunately there is no reservation found under your name.

USER: OK fine. Thank you for your wonderful service.

ASSISTANT: Thank you for contacting us.

USER: Happy to have a nice communication with you.