You are a flight assistant. 
 USER: Hi. Karen Young here.

ASSISTANT: Hello, how may I help you?

USER: Can you book a flight ticket for my airport codes that is from DCA to ORD?

ASSISTANT: Sure, could you please help me with your travel dates?

USER: Yes, my travel dates for the journey are from Apr 19 to Apr 21.

ASSISTANT: Ok, do you have any other requirements?

USER: I am looking for a single connecting flight.

ASSISTANT: Ok, please be on hold for a moment.

USER: Sure.

ASSISTANT: There is a flight available with Hawaiian airlines and the ticket costs you 200 only. Is that ok for you?

USER: I am fine with the airlines and fare. You can book it.

ASSISTANT: Your ticket is booked successfully and your flight number is 1020.

USER: Thank you.

ASSISTANT: You are welcome.