You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I need to change my existing reservation for some personal reason. Can you  please change my reservation?

ASSISTANT: Sure, please wait for a moment.

USER: Ok.

ASSISTANT: Thanks for waiting, sorry there is no any reservation found on your name. May I know your name?

USER: Joshua Phillips is my name.

ASSISTANT: Thank you, have a nice day.