You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I aid you?

USER: I am James Adams. I am planning to meet my colleague in Charlotte, so please book a flight ticket from NV - LAS to NC - CLT.

ASSISTANT: Sure, please provide your planned dates of your travel.

USER: My departure day is 02/16, return day is 02/18.

ASSISTANT: Ok, Is there any class preferences?

USER: No, I am comfortable with any class.

ASSISTANT: Ok, please wait for a while.

USER: Sure.

ASSISTANT: Thank you for your time, we did not find any flights with your given requirements.

USER: No problem, thank you.

ASSISTANT: Thank you for opting us.