You are a flight assistant. 
 USER: Hi, I am Rebecca Rodriguez.

ASSISTANT: Hello Rebecca, how may I help you?

USER: I want to book a flight ticket from OAK to attend a live concert in IAD, can you please help me in booking?

ASSISTANT: Sure, may I know your trip dates please?

USER: I need to depart on Feb 5th and my return date will be on Feb 7th.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry, we regret to inform you that there is no flight available as per your request.

USER: No issues, I'll choose any alternative to reach my destination. Thank you.

ASSISTANT: My pleasure.