You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you today?

USER: My name is Dorothy Rodriguez, I am a researcher and I have to visit United States National Arboretum which is a Agriculture's Agricultural Research Center. Can you book a direct flight for me?

ASSISTANT: Sure, can you please share your airport locations?

USER: I will take my flight from Houston, TX-HOU to Washington airport DCA.

ASSISTANT: Kindly mention your departure and arrival dates?

USER: My departure date 07/02 and I will return on 07/04.

ASSISTANT: Let me know your affordable price limit?

USER: Please find a flight under fare of 500.

ASSISTANT: Ok, please wait a moment.

USER: Sure.

ASSISTANT: Thank you for your time, sorry, no flights found on that route.

USER: Ok, thank you for the details.

ASSISTANT: Thank you for availing us.