You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: I am Mark Jones. Can you help me in booking my flight ticket from DEN to ORD?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My trip dates will be Jan 14th to Jan 16th.

ASSISTANT: Do you have any specifications?

USER: I need a lay by flight.

ASSISTANT: Can I know any other preferences?

USER: I need a depart flight which should  be in the afternoon.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry, there are no flights found.

USER: Its ok, thank you.

ASSISTANT: Thank you for reaching us.