You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you today?

USER: I am Emily Harris. Me and my family having a vacation trip in this month, we want to visit Carowinds it is in Charlotte, can you please book a flight ticket?

ASSISTANT: Sure, can you please provide the airport codes?

USER: I want to travel from LAS to CLT.

ASSISTANT: Can I know your travel dates?

USER: My departure day is 07/17 and return date is 07/19.

ASSISTANT: Ok, let me check for the availability of flight. Emily, I am sorry to inform you that there is no flight available at your requested dates.

USER: Oh it's ok. Thank you for your information.

ASSISTANT: You are welcome. Thank you for contacting us.