You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you today?

USER: My name is Cynthia Clark. I have a plan to meet my friend in Washington, can you help me for booking a flight ticket?

ASSISTANT: Sure, can you please share your airport codes?

USER: My travelling airport codes are from  DCA to ORD.

ASSISTANT: Please share your trip dates too.

USER: My travelling dates are from 10/23 till 10/25.

ASSISTANT: Sorry, no flights are available on your route.

USER: That's ok, thank you for checking.

ASSISTANT: Welcome, have a nice day.