You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I serve you today?

USER: Can you please book a ticket from SFO to ORD?

ASSISTANT: Sure, may I know your planned trip dates?

USER: My travelling dates are Aug 10 and Aug 12.

ASSISTANT: Kindly mention your name please?

USER: I am Dorothy White.

ASSISTANT: Is there any other requirements?

USER: I want a direct flight.

ASSISTANT: Unfortunately there is no flight found with your given information.

USER: Ok, Thank you for your service.

ASSISTANT: Thank you.