You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I assist you?

USER: My name is James Smith.

ASSISTANT: Happy to meet you James Smith.

USER: I need your help in booking a flight ticket from LAS to LAX, can you help me?

ASSISTANT: Can you help me by giving your dates?

USER: My travelling dates are from 04/19 to 04/21.

ASSISTANT: Ok, there is no flight for you with your request.

USER: It's ok. Thank you.

ASSISTANT: Thank you for choosing us.