You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: I am Richard Rodriguez. I would like to book a flight ticket to DEN to participate in the city tour. Can you book me a ticket from LAX?

ASSISTANT: Sure, We are here to help you. Can I know your travelling dates?

USER: I would start on 08/23 and return on 08/25.

ASSISTANT: Do you need any break?

USER: Yes.

ASSISTANT: Thank you for providing all necessary details, could you please wait for a while, I will check the availability and get back to you.

USER: Sure, take your own time.

ASSISTANT: Thank you for waiting, I regret to inform you that there is no flight obtained on your journey dates to book a flight ticket.

USER: That's alright, thanks for your assistance.

ASSISTANT: Thank you  for approaching us.