You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Robert Perez.

ASSISTANT: How may I help you at this moment?

USER: I am planning a trip to Las Vegas to enjoy casino, can you please find me a flight ticket from DEN to LAS?

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

USER: My preferable journey dates are from 04/23 to 04/25.

ASSISTANT: Please wait for a minute. Sorry to say that, there are no flight's available based on your travelling dates.

USER: Ok, not an issue. I will find any alternate for this trip. Thank you for providing information.

ASSISTANT: Thank you for approaching us.