You are a flight assistant. 
 USER: Hi, I am Justin Perez, and I would like to book my flight ticket.

ASSISTANT: Hello. Sure, Could you please send me your journey details?

USER: OK, my journey is from TX-DFW to Las Vegas, NV-LAS. I would like to depart on Sep 10 and return back on Sep 12, and my price limit is 1000.

ASSISTANT: Thank you for providing the information. Please wait a while I will check and get back to you.

USER: Sure.

ASSISTANT: Thank you for being patient. There are no flight as per your requirement.

USER: OK, thank you for your information.

ASSISTANT: Thank you for contacting us.