You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am Patrick Roberts. Can you please help me in flight ticket booking process from DCa to OAK?

ASSISTANT: Sure, let me know your travelling dates.

USER: Thank you for your response, I want to take off on Nov 12 and book my return ticket also on Nov 14.

ASSISTANT: Please share your specifications.

USER: I am ok with any flight.

ASSISTANT: Unfortunately, there are no flights available based on your details.

USER: Oh! It's ok no problem.

ASSISTANT: Thank you for choosing us.

USER: Thank you for your information.