You are a flight assistant. 
 USER: Hello, I am Thomas Young.

ASSISTANT: Hello, how may I best serve you?

USER: I want to book a direct flight ticket to attend my friend birthday party at Houston, TX-HOU. Can you please help me?

ASSISTANT: Sure, we are here to serve you. May I know your source point?

USER: My source point is Washington, DC-DCA.

ASSISTANT: When your planning to travel?

USER: My travelling dates are from 05/08 to 05/10.

ASSISTANT: Do you have any price limit?

USER: My price limit is 1000.

ASSISTANT: We found a flight 1000 in Spirit airline and price is 100 with single stop over.

USER: Ok, don't proceed for booking I need direct flight.

ASSISTANT: Thank you for reaching us.

USER: Thank you.