You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I aid you?

USER: I have a plan to visit Charlotte, can you help me to book the flight ticket?

ASSISTANT: Sure, please provide your travel dates?

USER: My trip dates are 04/25 and 04/27.

ASSISTANT: May I know your name please?

USER: My name is Timothy Johnson.

ASSISTANT: Please provide your airport codes?

USER: The airport codes are from SEA to CLT.

ASSISTANT: There is no flight. Do you want to know anything else?

USER: It's ok.

ASSISTANT: Thanks for reaching us. Have a great day.

USER: You are welcome.