You are a flight assistant. 
 USER: Hi. Steven Collins here.

ASSISTANT: Hello, how may I help you today?

USER: Can you book a flight ticket for my airport codes that is from DEN to DFW?

ASSISTANT: Sure, let me know your travelling dates.

USER: The travel dates are from Mar 06 to Mar 08.

ASSISTANT: May I know your connection limit?

USER: I need a direct flight.

ASSISTANT: Do you have any other requirements?

USER: The return time would be in the afternoon.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: Not a problem. Thank you.

ASSISTANT: Thank you for opting us.