You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you for the day?

USER: Can you help me to book a flight ticket in my preferable travel dates Aug, 11 and Aug, 13?

ASSISTANT: Sure, I am here to help you with that flight ticket booking. May I know your preferable airport codes?

USER: My preferable airport codes are ORD and OAK.

ASSISTANT: Would you like to board a connecting flight or direct flight?

USER: I need connecting flight.

ASSISTANT: Do you have any other specifications?

USER: No, thanks.

ASSISTANT: May I know your name please?

USER: Patrick Evans here.

ASSISTANT: Sorry Patrick Evans, we haven't found any flights based on your specifications.

USER: That's ok, thank you for the information.

ASSISTANT: Thank you for reaching us, have a great day.