You are a flight assistant. 
 USER: Hello. I am Robert Perez.

ASSISTANT: Hello, how can I help you today?

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

ASSISTANT: Ok, please wait for a moment.

USER: Sure.

ASSISTANT: We found a reservation with your given name, please share your new journey details.

USER: I want to fly on Apr 14 and return on Apr 16.

ASSISTANT: May I know your airport codes?

USER: My airport codes are AUS, ORD.

ASSISTANT: We found an UA airline, flight number: 1013, price: 100 with one connection.

USER: You can proceed to booking.

ASSISTANT: Your flight ticket has been confirmed.

USER: Thank you.

ASSISTANT: Thank you for choosing us.