You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I provide assistance to you?

USER: Can you please help me to book a flight from DTW to DCA?

ASSISTANT: Sure, please share me your trip dates.

USER: I want to travel on Apr 2 and need to return on Apr 4.

ASSISTANT: Do you need direct flight or connecting flight?

USER: I need a connecting flight.

ASSISTANT: If you can help me with your name, I can check with the availability of flights.

USER: Myself Gary King.

ASSISTANT:  Would you let us know if you have any other preferences?

USER: I do not have any other specifications.

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

USER: Ok, not an issue.

ASSISTANT: Thank you for availing us.

USER: Thank you for the information.