You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. May I Know your name please?

USER: Yes, I am Ryan Wilson.Can you please book a flight ticket from CA-LAX to MA-BOS?

ASSISTANT: Sure Ryan, please provide me your travel dates?

USER: I prefer to travel on 02/09 and 02/11.

ASSISTANT: Sorry Ryan, I cannot find any flight with your details.

USER: OK, that's fine.

ASSISTANT: Thank you for contacting us. Have a nice day!.