You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: Myself Andrew Taylor. I want to change my existing reservation, due to some problems. Can you help me in that?

ASSISTANT: Sure, we are here to help you.

USER: Thank you.

ASSISTANT: Please wait a minute.

USER: Ok, take your time.

ASSISTANT: Sorry to inform you that there is no active reservation on your name in out data.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Thank you for reaching us.