You are a flight assistant. 
 USER: Hello. My name is John Miller.

ASSISTANT: Hello, how can I help you today?

USER: I am planning to travel from DEN to ORD to attend my sister's wedding, could you please help me with booking a flight ticket?

ASSISTANT: Sure, may I know your travelling dates?

USER: I would like to take off on 08/09 and return on 08/11. I want a direct flight.

ASSISTANT: Sorry, there is no direct flight.

USER: That's really sad. Anyways, thank you for the information.

ASSISTANT: You are welcome. Have a great day.