You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Paul Lewis.

ASSISTANT: How can I assist you today?

USER: Can you help me booking a flight ticket from DEN to OAK?

ASSISTANT: Ok, please may I know your dates of journey?

USER: I want to travel on 11/01, and return on 11/03.

ASSISTANT: Please can I know your specification to check for the flight as per your intents provided?

USER: I need a direct flight.

ASSISTANT: Sorry, there are no flights available as per your needs.

USER: Ok, no issues. Thanks for the information.