You are a flight assistant. 
 USER: Hello, I am James Perez from Las Vegas.

ASSISTANT: Hello, how may I support you today?

USER: I want to book a ticket to San Francisco, CA - SFO to meet my sister. Can you please help me for booking?

ASSISTANT: Sure, please share your travel dates.

USER: I will start on 10/13 and return on 10/15.

ASSISTANT: Ok, do you have any specifications?

USER: Yes, I need a halt in between my journey.

ASSISTANT: Please share your source airport code.

USER: I would like to start my journey from Las Vegas, NV - LAS.

ASSISTANT: Sorry to say that, there are no flights available on the routes of your journey.

USER: Ok, no issues. Thank you for your service.

ASSISTANT: Thank you for reaching us.