You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I support you now?

USER: I am Christopher Smith. I am planning to attend for Cultural program in Washington, DC - DCA. Could you help me in booking a flight ticket from Oakland, CA - OAK?

ASSISTANT: Sure, I will help you with booking. Please share me your planned journey dates?

USER: My departure day is 08/25, return day is 08/27.

ASSISTANT: Do you need any halt in between the journey?

USER: Yes, I need a halt.

ASSISTANT: Please mention your budget for flight ticket?

USER: My budget is 1000.

ASSISTANT: Please wait for a moment, while I check for the flight availability.

USER: Sure.

ASSISTANT: Thank you for waiting, sorry there is no flight available on your given journey data.

USER: No problem, thank you.

ASSISTANT: Thank you for visiting us, we hope see you again.