You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you?

USER: My name is Paul Williams, and I would like to book my flight ticket.

ASSISTANT: Sure, Can you please provide me the details of your journey?

USER: My journey is from MI-DTW to DC-DCA. I would like to depart on Jan 30 and return back on Feb 1, please make sure that I need a direct flight with a price limit of 5000.

ASSISTANT: Please wait a moment, I will check and get back to you.

USER: Sure.

ASSISTANT: Thanks for waiting, We found no flights matching according to your provided details.

USER: May I know the details please? OK, thank you for your information.