You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how best I can serve you today?

USER: Please help me to change my recent reservation.

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: May I know your name please?

USER: Sharon Martin.

ASSISTANT: Ok, please be on hold.

USER: Sure.

ASSISTANT: Sorry, we could not find any reservation on your name.

USER: Thank you for your information.

ASSISTANT: Thank you for approaching us.