You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you today?

USER: Myself Debra Wright. I need to attend my fresher's party in my college, can you book a ticket for me?

ASSISTANT: Sure Debra. Please provide me your source and destination airport codes.

USER: My airport codes are OAK and DCA.

ASSISTANT: Can you tell me your preferred travel dates?

USER: My travel dates are from 05/01 to 05/03.

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

USER: It's fine.

ASSISTANT: Thank you for reaching us.

USER: Thank you for your immediate response.

ASSISTANT: You are welcome.