You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Mark Williams want to attend a seminar at Boston, can you book a ticket with price under 500?

ASSISTANT: Sure, could you please share your preferred journey dates?

USER: Sure, my travelling dates will be 03/28 and 03/30.

ASSISTANT: Can you help me with your source and destination airport codes?

USER: Yes, I want to fly from CLT to BOS.

ASSISTANT: There is a flight-1001 of Frontier airlines with price of 100 is available for you, shall I proceed?

USER: Yes, proceed with my booking.

ASSISTANT: Ok, your booking is done.

USER: Thank you.

ASSISTANT: Welcome.