You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you today?

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

ASSISTANT: Sure, I am here to help you.

USER: Thank you.

ASSISTANT: Please help by providing your name.

USER: I am Scott Campbell.

ASSISTANT: Thank you for giving your name, wait a moment I'll check and revert to you.

USER: Sure.

ASSISTANT: Thank you for waiting, I am sorry to say you that there is no reservation found under your name in our database.

USER: Ok, no problem. Thank you for your information.

ASSISTANT: Thank you for choosing us.