You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you today?

USER: I am planning to book my ticket from Washington, DCA to Houston HOU. Can you please help me with booking a flight ticket?

ASSISTANT: Sure, may I know your travel dates?

USER: My planned travel dates are from Feb 15 to Feb 17.

ASSISTANT: Please share me your name.

USER: Sure, myself Debra Thomas.

ASSISTANT: Do you have any specifications?

USER: My return time should be in the afternoon.

ASSISTANT: Sorry, there is no flight at this moment.

USER: That's ok, no problem. Thank you for the information.

ASSISTANT: Thank you.