You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I serve you?

USER: I am Virginia Brown. I want to go for site seeing in winter season, Can you please help me out?

ASSISTANT: Sure, I am here to help you. Can you please provide your journey details?

USER: My airport codes are Philadelphia, PHL to Las Vegas, Las on 12/07 to 12/09.

ASSISTANT: Please wait for a while I will check and revert you.

USER: Sure.

ASSISTANT: Thank you for  waiting. Sorry there are no flights available matching your requirements.

USER: Ok, Thank you for your information and service.

ASSISTANT: Thank you for reaching us.Have a nice day.