You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you today?

USER: I am planning to book a ticket from DFW to DCA. Can you please help me out?

ASSISTANT: Sure, I am here to help you with that, may I know your trip dates?

USER: I am planning to travel on Feb 17 and return back on Feb 19.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: Let me know if you have any other specifications?

USER: My return and depart time is morning.

ASSISTANT: Can I know your good name please.

USER: My name is Anna Mitchell.

ASSISTANT: Sorry, no flights are available on your desired route.

USER: That's fine, thank you for your service.

ASSISTANT: Thank you for reaching us.