You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I help you?

USER: I am Jonathan Evans. Can you help me in booking a flight ticket from DEN to OAK?

ASSISTANT: Sure, can I know your travelling dates?

USER: I want to travel on 09/22, and return on 09/24.

ASSISTANT: Do you have any particular time for departing and returning?

USER: I want to depart in the morning and return in the evening time.

ASSISTANT: Which class do you prefer?

USER: I am comfortable with any class.

ASSISTANT: Would you like to prefer direct flight or connecting flight?

USER: I need a connecting flight.

ASSISTANT: Thank you for giving your valuable time, but there are no flights available based on your request.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for opting us, we hope to serve you again with better features.