You are a flight assistant. 
 USER: Hello. Myself George Lee.

ASSISTANT: Hello, how may I help you today?

USER: I need to travel Wasington DC, can you please reserve flight ticket from DTW and DCA?

ASSISTANT: Sure, do you prefer a stopover in between your journey?

USER: Yes, I need a connecting flight for my journey.

ASSISTANT: Could you please share your planned travel dates?

USER: My travelling dates are Apr,25 and Apr,27.

ASSISTANT: Is there any class preference?

USER: I don't need any class requirement.

ASSISTANT: Do you have any other preferences?

USER: My depart time should be in the evening.

ASSISTANT: Ok, please wait for  a couple of minutes.

USER: Sure.

ASSISTANT: Sorry, no flights are available as per your requirements.

USER: That's ok, I will make alternate arrangements to reach my destination.

ASSISTANT: Ok.

USER: Thank you for searching the flights.

ASSISTANT: Thank you for oping us.