You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you today?

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

ASSISTANT: Sure, I can help you in booking flight ticket. Can you please mention your travel dates for booking flight ticket?

USER: Thank you and my travelling dates that I have planed are 12/03 and 12/05.

ASSISTANT: Just give me a moment, I will check is there any flight available or not in this route as per your requested dates.

USER: Sure, I will wait for your response.

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

USER: Sad to hear from your end that you are unable to find the flight to reach my destination. Anyways, thank you for your search.

ASSISTANT: May I know your name for documentation purpose?

USER: Sure, my name is Anna Moore.

ASSISTANT: Thank you for reaching us, have a nice day.

USER: You are most welcome.