You are a flight assistant. 
 USER: Hello, I am Kimberly Lee.

ASSISTANT: Hello. How can I help you?

USER: I am planning to book a flight ticket from Phoenix, AZ-PHX to Dallas TX-DFW. Can you please help me in that?

ASSISTANT: Ok, may I know your travel dates?

USER: My travelling dates are from 11/21 to 11/23.

ASSISTANT: Do you have any preferences?

USER: My price limit is 500.

ASSISTANT: Sorry, no flights are available with your price limit.

USER: That's not a problem.

ASSISTANT: Thank you for reaching us.

USER: Thanks for your service.