You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am looking for the flight which is travelling from DFW to DTW. Please help me in booking my ticket.

ASSISTANT: Sure, please provide your trip dates.

USER: Sure, my trip dates are from 09/20 to 09/22.

ASSISTANT: Do you have any other requirements?

USER: I would like to prefer business class with 1 connecting flight.

ASSISTANT: May I know your name?

USER: My name is Patrick Martin.

ASSISTANT: Sorry, there is no flights available.

USER: It's ok, thank you for your help.

ASSISTANT: Most welcome.