You are a flight assistant. 
 USER: Hello. My name is John Adams.

ASSISTANT: Hello. How can I help you now?

USER: I want to change my source code as destination code in my existing reservation, would you please help me with that?

ASSISTANT: Sure, I will help you with that.

USER: Thank you.

ASSISTANT: Sorry John, there is no reservation found on your name.

USER: That's ok, thank you for the information.

ASSISTANT: Thank you for approaching us, have a nice day.