You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you today?

USER: Need your assistance to change my existing reservation.

ASSISTANT: Sure, I will help you. May I know your name please?

USER: Sure, Please check my reservation on the name of Joshua Robinson.

ASSISTANT: Thanks for your name, please wait.

USER: Sure.

ASSISTANT: Thank you for waiting, no reservation was found on your name to change.

USER: That's Ok, thanks for your assistance.

ASSISTANT: Thank you for choosing us.