You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Jason Adams here.

ASSISTANT: How may I help you?

USER: I want to change my existing reservation from ORD to DCA, Can you assist me?

ASSISTANT: Sure, I will help you in booking your flight ticket. Could you please tell me your travel date?

USER: Sure, I would like to travel on 10/14 and 10/16.

ASSISTANT: Please hold on for a moment.

USER: Please take your finest time.

ASSISTANT: Delta airlines with flight number 1010 is available for you with single connection. Can I proceed?

USER: Yes, please book my ticket.

ASSISTANT: Your ticket has been booked successfully. Happy journey.

USER: Thank you for the sevice.

ASSISTANT: You are welcome. Thank you for visiting us.