You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: I have to attend a Live Concert at San Francisco, could you please help me with booking a flight ticket from DEN to SFO?

ASSISTANT: Sure, may I know your planned travel dates please?

USER: I would like to depart on July 27th and return on July 29th.

ASSISTANT: Do you have any class preference?

USER: I need a business class ticket.

ASSISTANT: Would you like to travel in a direct flight or a connecting flight?

USER: I am looking for a connecting flight.

ASSISTANT: May I know your good name please?

USER: I am Steven Baker.

ASSISTANT: Do you have any other specifications?

USER: I have no other specifications.

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

USER: Ok, not an issue.

ASSISTANT: Thank you for approaching us.

USER: Anyways, thank you for the information.