You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I aid you?

USER: Can you aid me to book my ticket from DCA to HOU?

ASSISTANT: Sure, can you please share your travel dates?

USER: My travel dates are Sep 3 and Sep 5 respectively.

ASSISTANT: Do you have any connection limit?

USER: Make sure that connection limit is single.

ASSISTANT: May I know your airline preference?

USER: No airline preferences for me.

ASSISTANT: Do you have any other requirements?

USER: I would like to depart in afternoon.

ASSISTANT: May I know your name to proceed further?

USER: Angela Walker here.

ASSISTANT: Sorry, there are no flights in this route as per your travelling details.

USER: No issue. Thank you.

ASSISTANT: Thank you for choosing us.