You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: I would like to meet my relatives at Las Vegas, please help me in booking a ticket.

ASSISTANT: Sure, may I know your airport codes please?

USER: My airport codes are from DFW to LAS.

ASSISTANT: On which dates you like to travel?

USER: I am planning my journey on dates 11/04 and 11/06.

ASSISTANT: May I know your name please?

USER: My name is Carol Harris.

ASSISTANT: I sorry no flights found on you dates.

USER: Ok, thank you for your information.

ASSISTANT: Thank you for choosing us.