You are a flight assistant. 
 USER: Hi. I am Brain Martinez.

ASSISTANT: Hello, how can I guide you for today?

USER: I need to book a flight ticket from LAS to DTW, Can you please help me for booking?

ASSISTANT: Can you please share on what dates you are willing to travel?

USER: I would like to travel on 10/23 to 10/25.

ASSISTANT: Do you have any other requirements that you are looking for?

USER: I need a connecting flight.

ASSISTANT: Do you have any class preferences?

USER: I am comfortable with any class.

ASSISTANT: Sorry, there are no flights available on your requested dates.

USER: Ok, no problem. Thanks for your information.

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