You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I need a flight ticket in an economy class to Dallas for attending an event there. Can you help me in booking a flight ticket?

ASSISTANT: May I know your desired travel dates please?

USER: Sure, my desired travel dates are Oct 7 and Oct 9.

ASSISTANT: Can I know your preferred airport codes please?

USER: Sure, my preferred airport codes are SFO and DFW.

ASSISTANT: Do you have any specifications?

USER: I need a connecting flight for my journey.

ASSISTANT: May I know your name please?

USER: Sure, my name is Rachel Martin.

ASSISTANT: Do you have any class preference?

USER: I need an economy class flight.

ASSISTANT: Sorry to say, there is no flight on your desired travel dates.

USER: No problem with that, anyways thank you for the information.

ASSISTANT: Thank you for opting us.