You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, please let me know your name?

USER: I want to travel Washington for attending a business meeting, can you please book a flight ticket from Detroit on 09/30? My name is Elizabeth Jackson.

ASSISTANT: Yes, I will search the flight to Washington.

USER: Thanks.

ASSISTANT: Could you please tell me the airport codes of Washington and Detroit?

USER: I want to take off from DTW airport and destination airport is DCA.

ASSISTANT: Ok, when you want to return from DCA?

USER: Please book my return ticket on 10/02.

ASSISTANT: Ok, give me a couple of seconds.

USER: Sure. Please make sure that I want a direct flight.

ASSISTANT: Sorry, there are no direct flights running to Washington.

USER: It's ok no problem, I will go with another airline. Thank you for your information.

ASSISTANT: You are welcome. Thank you for reaching our services. Have a nice day.

USER: Welcome.