You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

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

ASSISTANT: Sure, I am happy to help you. May I know your good name to proceed further?

USER: Jason Lopez.

ASSISTANT: Sorry, there is no active reservation on your name in our data.

USER: That's ok, thank you.

ASSISTANT: Thank you for contacting us.