You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how may I help you today?

USER: I want to change my reservation, help in that? I am Katherine Jackson.

ASSISTANT: Sure, I will help you with this. Sorry Jackson, there is no reservation found as per your name to change your reservation.

USER: That's ok, thank you for your help.

ASSISTANT: You are welcome and have a great day.