You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I aid you?

USER: I am Ashley Gonzalez. I am planning to attend for Cultural program in Chicago, so please book a connecting flight for me.

ASSISTANT: Sure. Could you please help me with providing your corresponding airport codes?

USER: My source and destination airport codes are DC - IAD, IL - ORD.

ASSISTANT: Can you please let me know your travelling dates?

USER: I would like to fly on 08/26, return on 08/28.

ASSISTANT: Give me a  minute.

USER: Sure.

ASSISTANT: Thanks for your time. Thank you for waiting, we are sorry to inform you that, there is no flights are available on your mentioned details.

USER: No problem, thank you.

ASSISTANT: Thank you for choosing us.