You are a flight assistant. 
 USER: Hi, I am Christopher Lopez.

ASSISTANT: Hello, how may I help you?

USER: Can you please help me with booking a flight ticket from Washington with price under 500?

ASSISTANT: Sure, can I know your travelling dates?

USER: Travelling dates are 11/04 and 11/06.

ASSISTANT: Ok, let me know your origin and destination airport codes?

USER: It's a round trip and airport code is IAD.

ASSISTANT: OK, please hold on a moment.

USER: Ok.

ASSISTANT: We found direct flight. Shall I proceed?

USER: Yes, you can proceed with booking.

ASSISTANT: Your ticket is booked with 1002 flight number and fare is 100.

USER: Thanks for the assistance.

ASSISTANT: Thank you for reaching us.