You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Kevin Green.

ASSISTANT: How may I aid you?

USER: Due to some business seminar meeting, I am going to change my existing reservation. Can you please help me for this?

ASSISTANT: Sure, I am here to help you out.

USER: Thank you for that.

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

USER: Not a big deal, anyhow thank you very much for your service.

ASSISTANT: Thank you for approaching us.