You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: I am John Harris. I am planning to book a ticket from DCA to LAS. Can you please help me out to book a ticket for me?

ASSISTANT: Sure, can you share your travelling dates?

USER: I would like to travel on 09/25 and return back on 09/27.

ASSISTANT: Give me a minute.

USER: Sure.

ASSISTANT: There is a connecting flight with number 1027 in airline Frontier, the fare is 100.

USER: That's fine, please proceed the booking.

ASSISTANT: Your ticket is reserved.

USER: Thank you for your service.

ASSISTANT: Thank you for opting us.