You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I best assist you now?

USER: I want to change my existing reservation. Could you help me with that?

ASSISTANT: Sure, I can change your reservation right now. Before that I need to know your good name please?

USER: Amy Rodriguez here.

ASSISTANT: Ok, Please allow me a moment to check for the previous reservation in our database.

USER: Ok.

ASSISTANT: Thanks for your time, we are sorry to say that there is no active reservation found on your name.

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

ASSISTANT: Thanks for opting us, wish you a great day.