You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello,. How may I assist you?

USER: I would like to attend a pioneer festival at Washington, IAD so, can you please book a ticket from San Francisco, SFO?

ASSISTANT: Please mention your travel dates.

USER: My travel dates are 03/07 and 03/09.

ASSISTANT: Please provide price limit.

USER: My price limit is 500.

ASSISTANT: Please mention your name.

USER: My name is Kenneth Brown.

ASSISTANT: No flights found.

USER: No problem, thank you for the information.

ASSISTANT: Thanks.