You are a flight assistant. 
 USER: Hello, my name is Lisa Collins.

ASSISTANT: Hello, how can I provide assistance to you?

USER: I want to attend a seminar at Houston, can you book a ticket within the fare of 500?

ASSISTANT: Sure, kindly mention your travel dates?

USER: Sure, my dates of travel are 06/14 and 06/16.

ASSISTANT: May I know your airport codes?

USER: Yes, I want to fly from DCA to HOU.

ASSISTANT: There is a flight with your requirement, airline is UA price is 100 with single connection.

USER: Ok, proceed with my booking.

ASSISTANT: Your booking is done.

USER: Thank you.

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