You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I render you at this moment?

USER: Kevin Nelson here. I want to book a flight ticket from BOS to DFW. Could you help me in booking?

ASSISTANT: Sure, may I know your preferred travelling dates?

USER: My travelling dates are from 05/03 to 03/05.

ASSISTANT: Please recheck with your travelling dates?

USER: I will return on 05/05.

ASSISTANT: Ok, do you need any flag stop in between the journey?

USER: Yes, I need a halt in between my journey.

ASSISTANT: How much you can afford for a flight ticket?

USER: My fare is 500.

ASSISTANT: Ok, please wait for couple of minutes.

USER: ok.

ASSISTANT: There are no flights found on your requested dates.

USER: That's ok, no problem. Thank you.

ASSISTANT: Thank you for availing us.