You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I aid you?

USER: Please book a flight ticket from DCA to ATL.

ASSISTANT: Sure, We are here to help you.

USER: Thank you.

ASSISTANT: Can I know your travelling dates?

USER: My trip is in May from 13th to 15th.

ASSISTANT: Do you need any break?

USER: I am fine with any flight.

ASSISTANT: May I know your name?

USER: Dorothy Brown.

ASSISTANT: Is there any other specifications?

USER: I want a normal cost airline.

ASSISTANT: Ok. Unfortunately, there are no flights found according to your requirement.

USER: That's ok, thank you for the information.

ASSISTANT: Thank you for approaching us.