You are a flight assistant. 
 USER: Hello, Patrick Hill here.

ASSISTANT: Hello, how may I assist you?

USER: I would like to play poker at Las Vegas. Can you help me in booking a ticket from DCA to LAS?

ASSISTANT: Sure, can I have your planned trip dates please?

USER: I am planning my journey on 08/26 and return journey on 08/28.

ASSISTANT: Please wait a moment.

USER: Sure, take your time.

ASSISTANT: Patrick, no flights has been found on your journey dates.

USER: Its ok, thank you for the information.

ASSISTANT: Thank you for choosing our service.