You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, what can I do for you today?

USER: I am planning to visit a Las Vegas LAS from DCA. Can you find a flight ticket for me?

ASSISTANT: Sure, let me know your travel dates?

USER: Ok, my planned trip dates are on Apr 17 and return on Apr 19.

ASSISTANT: Any requirements to be met?

USER: I need a single connecting flight.

ASSISTANT: Can you mention your name to proceed further?

USER: Ok, my name is Anna Young.

ASSISTANT: Sorry, no flights found as per your requirement.

USER: OK, not a problem. Thank you for your help.

ASSISTANT: Thank you for contacting us.