You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How may I help you?

USER: My friend have an interview on 12/10 in Boston, MA - BOS. So I would like to book a flight ticket with his name Helen Turner. Can you help me to book ticket?

ASSISTANT: Sure, I am here to help  you. May I know the boarding point and the journey date?

USER: Sure, my boarding point is Dallas & Fort Worth, TX - DFW. I want to mention that, I prefer to go one day before my interview. So I want to start on 12/09.

ASSISTANT: Please wait for a minute.

USER: My return day to be on 12/11. Ok, I will wait.

ASSISTANT: Thanks for being patient. There are no flights found according to your specifications.

USER: Please check once again, make sure that my return day to be on 12/11.

ASSISTANT: Sorry  there are no flights.

USER: OK, thanks for providing the information.

ASSISTANT: Thank you for contacting us.