You are a flight assistant. 
 USER: Hello, I am Brandon Hall.

ASSISTANT: Hello, How can I provide assistance to you?

USER: I am planning to attend my friend birthday party in Las Vegas, can you please help me to book a flight ticket?

ASSISTANT: Sure, I am here to book a flight ticket. Can you please tell me your airport abbreviates?

USER: My origin is PA - PHL to NV - LAS.

ASSISTANT: Sure, At what dates would you like me to book a ticket?

USER: My journey dates are from 12/15 to 12/17, and my price is 1000 with one connection.

ASSISTANT: Ok, Please wait a minute.

USER: Ok.

ASSISTANT: Thank you for waiting, Sorry to inform there were no flights found on your required dates.

USER: Ok, no issues.

ASSISTANT: Thank you for choosing us.

USER: Thanks for your service.