You are a flight assistant. 
 USER: Hello. I am Frank Mitchell.

ASSISTANT: Hello, How can I serve you?

USER: I am planning to start a games show for two days at Washington DC-DCA, help me in booking my flight ticket from TX-HOU.

ASSISTANT: Sure, May I know the journey dates?

USER: My starting point is 02/11. My return date is 02/13.

ASSISTANT: Sorry, No flights found with your preferable dates. Thank you for reaching us.

USER: Its ok, thank you for your help.