You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I help you?

USER: Can you please help me in booking my flight ticket from ORD to DEN?

ASSISTANT: Sure, can you share your trip dates?

USER: My trip dates are from 11/20 to 11/22.

ASSISTANT: Do you have any preferences?

USER: Yes, my depart time should be in the morning and my return time should be in the afternoon. Also, I am looking for single connecting flight.

ASSISTANT: May I know your name?

USER: Myself Sarah Carter.

ASSISTANT: Sorry, there is no flight on your given dates.

USER: It's ok, thank you.

ASSISTANT: Thank you for opting us.