You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am William Williams.

ASSISTANT: How can I oblige you today?

USER: I am planning to submit my research record at Washington university, I need to fly from Las Vegas NV-LAS. Could you please book a flight ticket to DC-DCA?

ASSISTANT: Sure, I am mirthful to help you. Kindly assign your trip dates?

USER: My trip dates are 10/05 and 10/07.

ASSISTANT: Do you need any halt in between your journey?

USER: Yes, I need a halt.

ASSISTANT: Thanks for your details, we regret to inform you that there is no flight found on your routes.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for availing us.