You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I want to celebrate my birthday at Las Vegas, please book my ticket from DEN to LAS.

ASSISTANT: Sure, may I know your name?

USER: Scott Jones here.

ASSISTANT: Can I know your travelling dates?

USER: My itinerary dates are Mar 5 and 7.

ASSISTANT: Can I know your connection limit?

USER: I need single stopover for my journey.

ASSISTANT: May I know your other preferences?

USER: I have no other preferences.

ASSISTANT: Sorry, there are no flights available on your travelling dates.

USER: No problem, thank you.

ASSISTANT: Thank you for choosing us.