You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

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

ASSISTANT: May I know your name please?

USER: Myself Michelle Turner.

ASSISTANT: No reservation found in our database as per your preferences at the moment.

USER: Not an issue. Thank you.

ASSISTANT: Thank you.