You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,.

USER: Myself Lisa Nelson.

ASSISTANT: Ok.

USER: I have planned for a round trip from BOS, could you please help me to book my flight ticket?

ASSISTANT: Please let me know your travelling dates in order to book a ticket.

USER: I want to depart on 04/19 and return on 04/21.

ASSISTANT: Please provide connections limit?

USER: I need single connection flight.

ASSISTANT: Please mention price limit?

USER: My price limit is 500.

ASSISTANT: Ticket is available with flight number 1020, airline JetBlue having price 100.

USER: That's perfect! You can proceed for booking the ticket.

ASSISTANT: Ticket is booked.

USER: Thank you very much for your help.

ASSISTANT: Thank you.