You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. Welcome to flight booking agency, what can I do for you now?

USER: I want to change an existing reservation, so please help me in changing the reservation.

ASSISTANT: Sure, I am oblige to help you with flight ticket modification process. Can I know your previous flight ticket booking name?

USER: Myself Linda Thomas.

ASSISTANT: Ok, please give me a moment.

USER: Ok.

ASSISTANT: I have checked based on your request but it is showing that there is no reservation found for the user to change it from my side.

USER: Not an issue. Thank you.

ASSISTANT: You are most welcome and thank you for approaching us.