You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: I need to travel DFW and LGA, can you reserve flight ticket?

ASSISTANT: Sure, can I know your trip dates?

USER: My travelling dates are Apr,13 and Apr,15.

ASSISTANT: Do you have any specifications?

USER: I prefer single connecting flight.

ASSISTANT: Can I know your good name?

USER: Myself Mark Davis.

ASSISTANT: Sorry, no flights are available in this route as per your requested dates.

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

ASSISTANT: Thank you for reaching us.