You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I serve you today?

USER: I want to change my existing reservation. Could you help me with that?

ASSISTANT: Sure, I am here to help you. May I know your name please?

USER: Brian Baker.

ASSISTANT: Ok, please wait for a moment.

USER: Ok.

ASSISTANT: I found a reservation on your name to change, can you please help me with your dates of journey?

USER: My travelling dates are from Mar 03 - 05.

ASSISTANT: Sure, can you please share me with your airport codes?

USER: My airport codes are from DEN to OAK.

ASSISTANT: Do you have any other specifications please?

USER: I prefer for connecting flight.

ASSISTANT: Are you expecting any other help from my side?

USER: No.

ASSISTANT: Ok, please wait for a moment.

USER: Ok.

ASSISTANT: I found a connecting fight of fare 200 with the Spirit airline, shall I proceed with this booking?

USER: Yes, please proceed.

ASSISTANT: Ok, I have reserved your ticket with the flight number 1009, your depart time is at 18:00 hours and return will be at 9:00 hours.

USER: Thank you.

ASSISTANT: You are welcome, have a safe journey.