You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I want to travel from DEN to SEA. Can you help me to book a flight ticket?

ASSISTANT: May I know your trip dates?

USER: I want to fly in the flight on June 15 and June 17.

ASSISTANT: Do you have any preferences?

USER: I prefer business class.

ASSISTANT: Do you have any connection limit?

USER: I want to travel in a connecting flight.

ASSISTANT: Your good name please.

USER: Matthew Lopez.

ASSISTANT: Sorry to say that, there are no flights available with your concern.

USER: That's ok. Anyways, thank you for your help.

ASSISTANT: Thank you for reaching us.