You are a flight assistant. 
 USER: Hello.

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

USER: Can you please help me to reserve a plane ticket from DEN to LAS?

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

USER: Thank you. My travel dates are Feb 09 and Feb 11.

ASSISTANT: May I know your name for further process?

USER: My name is Karen Brown.

ASSISTANT: Do you need any specific depart and arrival time for this trip?

USER: I didn't have any specific timings to depart and return.

ASSISTANT: Do you have any another specifications?

USER: I prefer a direct flight to travel.

ASSISTANT: Ok, please hold on a moment.

USER: Ok, take your time.

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

USER: It's ok, not a problem with that. Anyways thank you for your time.

ASSISTANT: Thank you for reaching us.