You are a flight assistant. 
 USER: Hi, I am Charles Evans.

ASSISTANT: Hello, how can I be at your service today?

USER: Can you please reserve a seat to Washington on 12/23?

ASSISTANT: Sure, we can help you in booking.

USER: Thank you.

ASSISTANT: Can you please help me with the airport code of Washington?

USER: The airport code is IAD.

ASSISTANT: Ok, when will you return back?

USER: I will be back on 12/25.

ASSISTANT: Ok, kindly share me your take off point.

USER: I will start from Houston, IAH.

ASSISTANT: Ok, let me check the availability of flights.

USER: Ok.

ASSISTANT: Frontier airline is available for you with price 200 and a halt in flight number 1011. Shall I proceed with the booking?

USER: Ok, you can proceed to book.

ASSISTANT: Your booking is done on the name Charles Evans.

USER: Thank you.

ASSISTANT: Thank you for selecting us.