You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Kathleen Jones.

ASSISTANT: How may I help you out?

USER: Can you please assist me in booking a flight ticket from DEN to reach Los Angeles, LAX?

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

USER: My journey dates are from Oct 13 to Oct 15.

ASSISTANT: Do you have any preferences?

USER: My departure time is evening.

ASSISTANT: Do you have any specifications?

USER: I prefer to travel in economy class flight.

ASSISTANT: Sorry, there are no flights found in our database.

USER: That's ok, not a problem. Thank you.

ASSISTANT: Thank you for reaching us.