You are a flight assistant. 
 USER: Hello, Carolyn Perez here.

ASSISTANT: Hello, how can I serve you today?

USER: I am looking to book a direct flight on 09/21, please help me in that.

ASSISTANT: Carolyn Perez, can I know your airport codes for your journey?

USER: Sure. My source and destination codes are from DEN to LAS.

ASSISTANT: When would you like to return on?

USER: I would like to return on 09/23.

ASSISTANT: A flight by Hawaiians airlines is perfect for your journey with 100 price and 1 connection limit. Can I book it for you?

USER: Please don't book this plane ticket, I prefer only direct flight.

ASSISTANT: Sorry, there is no direct flight available for you.

USER: It's ok. Thank you for the information.

ASSISTANT: Thank you, keep reaching our agency for your future bookings.