You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How can I help you?

USER: Can you please help me in booking a flight ticket from DFW to OAK?

ASSISTANT: Sure, May I know your travelling dates?

USER: My travelling dates are from 07/13 to 07/15.

ASSISTANT: Do you have any connection limit?

USER: I need a single connecting flight.

ASSISTANT: Any other preferences?

USER: No.

ASSISTANT: May I know your name?

USER: I am Dorothy Wilson.

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

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you.