You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: Myself Lisa Roberts.

ASSISTANT: How can I assist you?

USER: I want to visit Washington next month, can you please book a flight ticket from OAK airport?

ASSISTANT: Sure Lisa, can I know the travel dates please?

USER: My departure date is 08/29 and please book this flight ticket on my name 08/31.

ASSISTANT: Could you provide destination airport code please?

USER: My destination airport is DCA.

ASSISTANT: Ok, wait a moment please.

USER: Ok.

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

USER: Oh! It's ok no problem, I will go with another airline.

ASSISTANT: Thank you for choosing us.

USER: Thank you for your information.