You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Larry Roberts here.

ASSISTANT: How may I assist you?

USER: I want to travel from DFW to HOU for a birthday function.

ASSISTANT: Ok, may I know your trip dates please?

USER: My preferable dates are from 12/21 to 12/23. Make sure that price limit should not exceed 200.

ASSISTANT: There is a flight for you with number 1006 in Frontier airline.

USER: That's great, please book the ticket.

ASSISTANT: Ok, your ticket has been booked.

USER: Thank you for your help.

ASSISTANT: Thank you for approaching us.