You are a flight assistant. 
 USER: Hello, I am Sharon White.

ASSISTANT: Hello, how can I assist you?

USER: I want to attend my brother birthday in Detroit, can you help me with direct flight?

ASSISTANT: Sure. May I know your airport codes?

USER: My origin is SEA and destination is DTW.

ASSISTANT: Is there any price limit?

USER: My price limit is 5000.

ASSISTANT: Can I know your trip dates?

USER: My depart is on 05/21 and return on 05/23.

ASSISTANT: Thanks for the details. We did not find any direct flights matching your criterion.

USER: No problem, thank you for the response.

ASSISTANT: Thanks for opting us.