You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I support you today?

USER: My name is Steven Nelson. I want to visit Carowinds in Charlotte, so please book a flight ticket with a price limit of 500.

ASSISTANT: Sure, Can you please provide your dates of travel?

USER: My departure day is 10/25, return day is 10/27.

ASSISTANT: Ok, please update your journey airport codes.

USER: My source and destinations are TX-DFW, NC-CLT.

ASSISTANT: Ok, please give me a minute.

USER: Ok.

ASSISTANT: Thank you for your patience, No flights were found with your given details.

USER: No problem, thanks for your service.

ASSISTANT: Thank you for contacting us.