You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am John Hernandez.

ASSISTANT: Nice to meet you John.

USER: I would like to meet my friend at Charlotte, can you help me to book a flight ticket from LAX to CLT?

ASSISTANT: Sure, tell me your travel dates please?

USER: I am travelling from Apr 16 to Apr 18.

ASSISTANT: Please wait.

USER: Sure, please book my flight ticket depart time evening and return time morning.

ASSISTANT: Sure. Thanks for waiting. But I am sorry to say that there are no flights available.

USER: No problem, thank you for the information.

ASSISTANT: Thank you.