You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,.

USER: I am Nicholas Martinez.

ASSISTANT: How can I amend you?

USER: Can you help me in booking a flight ticket, as I want to start my journey on 06/08 and returns on 06/10.

ASSISTANT: Sure, May I know your airport codes?

USER: I would have to go to attend for a meeting which is to be held at DCA from SFO.

ASSISTANT: Wait for a while.

USER: Sure.

ASSISTANT: Thanks for your time. There is no flight found with your specified request. Thank you for reaching us.

USER: Thank you for helping me in booking a ticket.