You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I aid you now?

USER: I am Paul Turner. I want to book a flight on 07/15 to attend my cousin birthday in Las Vegas.

ASSISTANT: Ok.

USER: Can you help me in booking a flight ticket?

ASSISTANT: Sure. May I know your journey dates?

USER: I will return from NV - LAS on 07/17.

ASSISTANT: Let me know your source code.

USER: My source code is NY - EWR.

ASSISTANT: Thanks for your time. We found that there was no flight that matches with your information.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your help.