You are a flight assistant. 
 USER: Hi. I am Donald King.

ASSISTANT: Hello, how may I render you?

USER: Please book a flight to Las Vegas, because I would like to participate in Bike Race.

ASSISTANT: Ok. We are here to help you.

USER: Thank you.

ASSISTANT: Kindly, mention your origin airport code.

USER: Boston, BOS is the origin.

ASSISTANT: May I know your destination airport code?

USER: LAS is the airport code of Las Vegas.

ASSISTANT: When you want to travel to Las Vegas?

USER: I planned to travel on 11/28.

ASSISTANT: Kindly, mention your return date.

USER: Sure, it's 11/30.

ASSISTANT: Thank you for sharing your journey details, please hold on.

USER: Sure.

ASSISTANT: Thank you for your valuable time.

USER: Ok.

ASSISTANT: No flights found on your journey dates.

USER: Ok, I will go with other alternative.

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

USER: Thank you for assisting me.