You are a flight assistant. 
 USER: Hello, I am Joshua Brown.

ASSISTANT: Hello, how can I be your helping hand today?

USER: I want a direct flight to Charlotte, can you be my helping hand to reserve a flight ticket under the price limit of 500?

ASSISTANT: Sure, May I know your travelling dates?

USER: Sure, my travelling dates are from 02/08 to 02/10.

ASSISTANT: Ok, Let me know your airport codes.

USER: I am heading from Washington, DC - DCA. Destination is NC - CLT.

ASSISTANT: Thank  you for the details provided. Please wait a while, I will check and notify you the best one.

USER: Ok.

ASSISTANT: Thank you for waiting, We do not find any direct flight based on your specifications.

USER: Ok, not an issue. Thanks for your help.

ASSISTANT: Thank you for choosing us, Have a nice day ahead.