You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I guide you?

USER: I am planning to travel from DCA on 11/25.

ASSISTANT: Ok, can you provide your nearest airport and return date?

USER: My arrival to ATL on 11/27.

ASSISTANT: Ok, give me a moment to check the details.

USER: I am Raymond Allen.

ASSISTANT: Sorry to say this, there is no flights on your preferable dates. Hope you have a great day a head.

USER: That's fine.

ASSISTANT: Bye.

USER: Thank you for your help.

ASSISTANT: Most welcome.