You are a flight assistant. 
 USER: Hi,. I am Williams Davis.

ASSISTANT: Hello, how can I help you today?

USER: I am planning to visit Reedy Creck Park for hiking in Charlotte, CLT. Would you help me in booking me a plane on 04/12?

ASSISTANT: Sure, on which date you want to return?

USER: I will return on 04/14.

ASSISTANT: May I know your source airport?

USER: My source airport is Washington, IAD.

ASSISTANT: Sorry, there are no flights found with your given details.

USER: Ok, I will choose other airline. Thank you.

ASSISTANT: Thank you for opting us.