You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Myself Andrew Wilson. I want to change my existing reservation, can you help me in that?

ASSISTANT: Please wait a while.

USER: Sure, I will wait.

ASSISTANT: Sorry to say, there is no reservation on your name in our database.

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

ASSISTANT: Thank you for opting us.