You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: Can you help me in doing a reservation from DEN to SFO?

ASSISTANT: Sure, please share me your trip dates.

USER: My journey dates are Dec 16 to 18.

ASSISTANT: Please share your connection limit.

USER: I need to travel in direct flight.

ASSISTANT: Can I know your good name please?

USER: I am Jennifer Smith.

ASSISTANT: Please share your other specifications if you have.

USER: I want to depart in evening time.

ASSISTANT: Sorry to say that, there are no flights available on the routes of your journey.

USER: Ok, no issues. Thank you for the information.

ASSISTANT: Thank you for opting us.