You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I am planning to change an existing reservation, due to some urgent work. Can you please help me out?

ASSISTANT: Ok, I am here to help you with that.

USER: Thank you.

ASSISTANT: Can I know your name?

USER: I am Andrew Phillips.

ASSISTANT: Please wait for a minute.

USER: Sure.

ASSISTANT: We are regret to say that, there is no active reservation found in our database.

USER: That's fine, thank you for your service.

ASSISTANT: Thank you for consulting us.