You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I aid you today?

USER: I am Jonathan Hernandez and I want to change my existing reservation.

ASSISTANT: Sure, Jonathan Hernandez, we are here to help you. Please wait for a moment.

USER: OK.

ASSISTANT: Thanks for your patience, we did not find any existing reservation specified on your name.

USER: OK, Thank you for your information.

ASSISTANT: Thanks for choosing us. Have a nice day.