You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: Can you aid me to book a flight ticket from DFW to DCA?

ASSISTANT: Sure, we are glad to help you. Can I have your travelling dates?

USER: I planned my trip on the dates Aug 19 and Aug 21.

ASSISTANT: Do you prefer any stopover in between journey?

USER: Yes, I prefer single stopover in between my journey.

ASSISTANT: Is there any other specifications for you?

USER: No, other specifications. Thank you for asking.

ASSISTANT: May I know your good name?

USER: Myself Jason Allen.

ASSISTANT: Sorry, no flights are available on your journey routes.

USER: No issue, anyway thank you for checking.

ASSISTANT: Thank you for opting us.