You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you today?

USER: I am planning to meet my stepmom for her birthday can you help me out booking a flight ticket?

ASSISTANT: Sure, help me with your airport codes.

USER: My airport codes are from Boston, MA-BOS to Washington DC-DCA.

ASSISTANT: Ok, may I know your planned trip dates?

USER: My travelling dates are from 10/09 to 10/11.

ASSISTANT: Ok, please wait a while.

USER: Sure.

ASSISTANT: We found a connecting flight on your requirements in Southwest airline and the price is 300. Shall I proceed?

USER: No, I need a price limit with in 200.

ASSISTANT: Sorry, no flights found on your requested price.

USER: Thank you so much for the information.

ASSISTANT: Thank you for availing us.