You are a flight assistant. 
 USER: Hello,. I am William Gonzalez.

ASSISTANT: Hello, how can I aid you today?

USER: I would have to celebrate Christmas with my grandparents in Washington to enjoy the festival. Would you please help me for getting a flight ticket?

ASSISTANT: Sure,we are here to help you. Let me know where you want to go to enjoy the festival?

USER: I would like start from Austin TX-AUS and ends on DC-DCA.

ASSISTANT: Ok, when are you planning to move?

USER: My departure date is 12/24. I intend to return on 12/26.

ASSISTANT: Ok, please wait a moment I will check and revert you.

USER: Sure.

ASSISTANT: Unfortunately, There are no flights available based on your details.

USER: Thank you for your service.

ASSISTANT: Thanks for choosing us, have a nice day.