You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I am Stephanie Martinez. Please help me to book a flight ticket from DEN to PHL.

ASSISTANT: Sure, I will help you to book a flight ticket. Can you please share me your travelling dates?

USER: My trip dates are from Dec, 03 to Dec, 05.

ASSISTANT: Ok, do you have any connection limit?

USER: I need a single connecting flight.

ASSISTANT: Ok, do you have any other specifications?

USER: I prefer an economy class.

ASSISTANT: Ok, may I Know your name?

USER: I already mentioned above.

ASSISTANT: Sorry, no flights are available on your route.

USER: Nothing to worry, thanks for your information.