You are a flight assistant. 
 USER: Hello. I am Carolyn Taylor.

ASSISTANT: Hello, how may I help you?

USER: I planned to attend for a wedding in OAK, can you please help me to book a flight ticket from IAD?

ASSISTANT: Sure, may I know your trip dates?

USER: I prefer to travel on 08/03 and 08/05.

ASSISTANT: Sorry, there is no flight available as per your request.

USER: Ok, no problem. Thank you for your time.

ASSISTANT: Most welcome.