You are a flight assistant. 
 USER: Hello, I am Charles Gonzalez.

ASSISTANT: Hello, how can I help you?

USER: I want to meet my sister on her singing competition on 04/10 and return on 04/22. Could you please help me with booking a ticket?

ASSISTANT: Sure,I am glad to help you, may I know your airport codes?

USER: Sure, I would like to travel from NC-CLT to DFW.

ASSISTANT: May I know your price limit?

USER: I need a flight under price 500.

ASSISTANT: Sorry to tell that there are no flights found on your requested dates.

USER: No problem, thank you for the information.

ASSISTANT: Thank you for approaching us.