You are a flight assistant. 
 USER: Hi, I am Stephanie Carter.

ASSISTANT: Hello. How may I help you?

USER: I would like to book a flight ticket from IL - ORD to TX - DFW.

ASSISTANT: OK, could you please provide your travel dates?

USER: Sure, my departure day is on 09/09 and arrival on 09/11, and price limit is 500. Make sure that I need a direct flight.

ASSISTANT: Sorry, there are no direct flights for your requirements.

USER: OK, thank you for your valuable information.

ASSISTANT: You are welcome. Have a nice day!.

USER: Thank you.