You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am Andrew Robinson. I want to change my existing reservation due to bad weather conditions. Can you please help me with this?

ASSISTANT: Please wait a while.

USER: Sure.

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

USER: Ok, no problem. Thank you for checking.

ASSISTANT: Thank you for opting us.