You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I assist you?

USER: I am Justin Miller and I want to change my existing reservation.can you help me out with this?

ASSISTANT: OK, please wait for a moment.

USER: Sure.

ASSISTANT: Thanks for waiting, sorry there are no flight found as your name.

USER: Thanks for the information.

ASSISTANT: Thanks for connecting us, have a nice day.