You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: My appointment with my family doctor has been postponed. Can you please change my existing reservation?

ASSISTANT: Sure, please wait.

USER: Ok.

ASSISTANT: May I know your name?

USER: Jeffrey Brown.

ASSISTANT: We found a reservation, please share your new details.

USER: My origin is CA - OAK and destination is TX - IAH. I would like to depart on 09/12 and return on 09/14. Price should not exceed 500.

ASSISTANT: Okay , thanks for your your details.

USER: I need single connection.

ASSISTANT: Ok. We found a flight on southwest airline with 100 fare. Flight number as 1001 and with single connection.

USER: Please book this.

ASSISTANT: Your ticket has been confirmed on Southwest airline.

USER: Thank you for booking my ticket.

ASSISTANT: Thank you for opting us, have a good day.