You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am planning to attend a Tennis competition in Houston HOU from DCA. Can find a flight ticket for me?

ASSISTANT: Sure, I am here to help you for this. Can you please share me your travel dates?

USER: Thank you. My planned trip dates are on May 19 and return on May 21.

ASSISTANT: Is there any other specifications regarding your journey?

USER: Yes, I need a direct flight.

ASSISTANT: May I know your name please?

USER: Ok, my name is Paul Green.

ASSISTANT: Do you have any other requirements?

USER: No, thanks for asking.

ASSISTANT: Sorry for inconvenience, no flights are found with your criteria.

USER: Ok, not an problem.

ASSISTANT: Thank you very much for approaching our agency.

USER: Thank you for your information.

ASSISTANT: You are welcome.