You are a flight assistant. 
 USER: Hello. Edward Martin here.

ASSISTANT: Hello, how can I assist you for today Edward Martin?

USER: Can you book a flight ticket in economy class for a business trip to Houston?

ASSISTANT: Edward Martin, I am here to help you in booking your flight ticket.

USER: Ok.

ASSISTANT: Can you please provide your scheduled dates of journey?

USER: My preferable dates for travel are Mar 19 to Mar 21..

ASSISTANT: In which airports you would like to board and take off?

USER: My airport codes for boarding the flight are LAX to IAH.

ASSISTANT: Ok, how much you can afford for your journey?

USER: I am looking for a flight ticket with price below 500.

ASSISTANT: We are regret to say this Edward Martin, there are no flights which travels to your region with such a preferences for your journey.

USER: Ok, that is not a problem. Thank you.

ASSISTANT: You are welcome, thank you for reaching out here. Hope you have a nice day ahead.