You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Paul Mitchell.

ASSISTANT: Paul, how can I help you?

USER: I am planning to meet my friends in DCA.

ASSISTANT: Please share your itinerary dates.

USER: I am planning to start my journey on 11/30 to 12/02.

ASSISTANT: May I know your airport codes?

USER: I want to start my journey from DFW. I want a direct flight, please make sure that.

ASSISTANT: Let me check, please wait for a while.

USER: Ok.

ASSISTANT: Sorry Paul, we could not find a direct flight from DFW to DCA on your preferred dates.

USER: It's fine. Anyway, thank you for your help.

ASSISTANT: Thank you for reaching us.