You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I be there for you?

USER: Joshua Anderson here. I want book a flight ticket from SFO to DFW.

ASSISTANT: Sure, please let me know your preferred dates of trip.

USER: My itinerary travel dates are Nov 15 and Nov 17.

ASSISTANT: Do you have any connecting limit?

USER: I would board with single connection flight.

ASSISTANT: Ok, please give me a moment.

USER: Sure.

ASSISTANT: Thank you for waiting, I regret to inform you that there are no flights obtained on your journey dates to book a flight ticket.

USER: No problem, thank you for your time.

ASSISTANT: Thank you for opting us.