You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, how may I serve you?

USER: Please book a flight to Boston, MA-BOS from Las Vegas, NV-LAS for holiday vacation.

ASSISTANT: Sure, may I know your journey dates?

USER: Depart by 08/23 and return on 08/25.

ASSISTANT: To proceed booking I need your name.

USER: I am Kimberly Collins.

ASSISTANT: Please wait for a while.

USER: Ok.

ASSISTANT: Thanks for waiting, there is no flight found on your given requirements.

USER: Thanks.