You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello.

USER: Joseph Lewis here.

ASSISTANT: How may I assist you?

USER: I would like to prefer a flight with lay-by option for my business trip to Washington. Can you book the flight ticket?

ASSISTANT: Sure, can I know your travelling dates/.

USER: The travel dates are from June 09 to June 11.

ASSISTANT: May I know your travelling airport codes?

USER: The airport codes are from IAH to DCA.

ASSISTANT: Any specifications needed?

USER: No.

ASSISTANT: Please wait a moment, let me check with your details.

USER: Sure.

ASSISTANT: There is a direct flight with the price 100 in Sprint Airlines, can I proceed with the reservation?

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

ASSISTANT: Your ticket has been reserved with the flight number 1000.

USER: Thank you.

ASSISTANT: Thank you for choosing our service.