You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: Can you please book a flight ticket from JFK to DEN?

ASSISTANT: Sure, I am here to help you. May I know your planned trip dates?

USER: Thank you, my travelling dates are Dec 30 and  Jan 01.

ASSISTANT: Do you have any connection limit preference?

USER: Yes, I need a break in between the journey.

ASSISTANT: Do you have any class preference?

USER: No, I am comfortable with any class.

ASSISTANT: Are you looking for any time preference?

USER: Yes, I want to depart at evening.

ASSISTANT: Do you have any other specifications? Could you help me with your name please?

USER: I am looking for normal cost airlines, can you please check for the Delta airlines? Yes, my name is Gregory Collins.

ASSISTANT: I am sorry to say that there are no flights available on this route for the given dates.

USER: That's fine, thank you for the response.

ASSISTANT: Thank you for reaching us.