You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: David Perez here.

ASSISTANT: In which way I can aid you at this moment?

USER: I have planned a trip with my students to enjoy the holidays in water world in the month of January, so please book an advance flight ticket for me to DEN from my home town SFO?

ASSISTANT: Sure, I am happy to aid you in booking flight ticket. Could you please mention your preferable travel dates for booking flight ticket?

USER: Thank you for taking my request into consideration. I am planning to leave my location on 01/13 and please book my return ticket also on 01/15.

ASSISTANT: Ok, please hold on a moment, I will check flight availability in this route.

USER: Take your time but try to bring a best flight in my route.

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

USER: Oh! Sad to hear that. Anyway, I will find another alternative to complete my journey. Thank you for the information.

ASSISTANT: Thank you for reaching us, have a good day David Perez.

USER: Welcome.