You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: I am Timothy Green. Can you help me to book a flight with 200 price limit?

ASSISTANT: Sure Green, can I know the travel dates please?

USER: My preferred travelling dates are 04/05 and 04/07.

ASSISTANT: Could you provide the airport codes please?

USER: My airport codes are BOS and ORD.

ASSISTANT: There is a flight in UA airline with price 100, can I book it?

USER: Yes, proceed.

ASSISTANT: Your ticket has been booked with flight number 1023.

USER: Thank you.

ASSISTANT: Thank you for approaching us.