You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: My meeting got postponed as of now, so I need to change my existing reservation.

ASSISTANT: Sure, I am here to assist you. May I know your name please?

USER: Jeffrey Thompson is my name.

ASSISTANT: Wait a moment please.

USER: Take your time, I will wait.

ASSISTANT: Jeffrey Thompson, we haven't found any reservation under your name in our database.

USER: That's ok, thank you.

ASSISTANT: Thank you for choosing us.