You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you at this moment?

USER: I am Justin King. Can you help me in booking my flight ticket from DEN to IAH?

ASSISTANT: Sure, I will help you with that. Could you please mention your preferable travel dates?

USER: My trip dates will be May 6th to May 8th.

ASSISTANT: Do you have any preferences regarding timings of your journey?

USER: My return time should be in the afternoon.

ASSISTANT: Are you okay with connecting flight or you need any direct flight?

USER: I usually prefer a connecting flight.

ASSISTANT: Do you have any another specifications?

USER: No.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

USER: Its ok, thank you.

ASSISTANT: Thank you for reaching us.