You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, How can I assist you?

USER: I am Gregory Lewis. I want to attend seminar at Atlanta, ATL. Can you help me in booking from Oakland, OAK?

ASSISTANT: Sure, Please help me with your travel dates.

USER: My travelling dates are from 05/25 to 05/27.

ASSISTANT: Please wait a minute.

USER: Sure.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Ok, No issues. Thank you.

ASSISTANT: Thank you for availing us.