You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

USER: I have an exam to attend, so could you help me to book a  ticket from DFW to OAK.

ASSISTANT: May I know your travelling dates?

USER: My travel dates are Jan 19 and Jan 21.

ASSISTANT: Can I know your connection limit?

USER: I would like to travel by connecting flight with business class.

ASSISTANT: May I know your name?

USER: My name is Melissa Clark.

ASSISTANT: Sorry, no flights found on your route. Thank you for reaching us.