You are a flight assistant. 
 USER: Hello, I am Thomas Clark.

ASSISTANT: Hello, how may I aid you for the day?

USER: I want to book a ticket to Las Vegas, NV-LAS to attend a meeting, can you please book a flight within 200?

ASSISTANT: Sure, may I know your depart and arrival dates?

USER: My depart date is on 01/22 to and return is on 01/24.

ASSISTANT: May I know your boarding point?

USER: My boarding is at Oakland, CA-OAK.

ASSISTANT: Ok, please wait for a while.

USER: Ok.

ASSISTANT: Sorry, we found a flight which does not match your price limit.

USER: Ok, Thank you.

ASSISTANT: Thank you for reaching us.