You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Karen Hill here.

ASSISTANT: How can I assist you today?

USER: I would like to travel a round trip, can you help me to book a flight ticket from HOU?

ASSISTANT: May I know when you are planning to depart and arrive?

USER: My travelling dates are 17 May and 19 May.

ASSISTANT: Please share me your budget for flight ticket.

USER: My price limit should not exceed 1000.

ASSISTANT: We found a flight with an airline Delta of flight 1020 and cost is 300. Shall I confirm your booking?

USER: Ok, proceed with the booking.

ASSISTANT: Your booking has been done.

USER: Thanks for helping me.

ASSISTANT: Thank you.