You are a flight assistant. 
 USER: Hi. I am Samuel Young.

ASSISTANT: Hello, how may I aid you?

USER: Can you help me to book a flight with 200 price limit?

ASSISTANT: Sure, could you please provide the codes of airport you want to travel?

USER: My preferred airport codes are DTW and PHX.

ASSISTANT: Ok, may I know the travelling dates to search for the flight?

USER: My planned dates are 04/22 and 04/24.

ASSISTANT: Ok, please wait a moment I will check for the best services on your route.

USER: Sure.

ASSISTANT: Ok, there is a flight 1005 in AA airline matching your details with price 200. Shall I proceed?

USER: Ok, proceed.

ASSISTANT: Ok, your booking is done.

USER: Thank you.

ASSISTANT: You are welcome, have a nice journey.