You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how can I assist you?

USER: I am Richard Lee. We are planning to go Benjamin Franklin Bridge in Philadelphia with my childhood friends to explore the global culture. Could you please book a ticket for me?

ASSISTANT: Ok, may I know your airport codes?

USER: Sure, destination airport is NC-CLT and source airport is PA-PHL.

ASSISTANT: To proceed booking I need your travelling dates.

USER: My travelling dates are 05/10 and 05/12. I need a direct flight.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Thanks for waiting, there is no direct flight available with your requirements.

USER: Ok, no issue. Thank you for your information.

ASSISTANT: Thank you.