You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I help you now?

USER: I am Mary Walker. I want to book a flight ticket with a price limit of 200, will you help me in booking a flight ticket?

ASSISTANT: Sure, I will help you with booking. May I have your travel dates?

USER: My departure is 10/29 and return date on 10/31.

ASSISTANT: Please provide me your airport codes?

USER: I need a direct flight to visit Lake Travis. My source from MN - MSP and destination to TX - AUS.

ASSISTANT: Please wait while I search for the flight.

USER: Sure.

ASSISTANT: Thanks for the information, sorry to inform you there is no any flight available on your journey details.

USER: Not an issue. Thanks for your service.

ASSISTANT: Thank you for contacting us, have a nice day.