You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

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

ASSISTANT: May I know your travelling dates?

USER: Sure, my travel dates are from Apr 19 to Apr 21.

ASSISTANT: Please let me know your connection limit?

USER: I would prefer connecting flight for my trip.

ASSISTANT: Do you have any other requirements?

USER: No.

ASSISTANT: Can I know your name please?

USER: Myself Karen Young.

ASSISTANT: Sorry, no flights available on your route.

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thank you for reaching us.