You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello,. May I know your name?

USER: Sure, I am Donna Garcia.

ASSISTANT: How Can I help you today?

USER: I want to book a flight ticket from origin Atlanta, GA- ATL to Dest  Dallas & Fort Worth, TX- DFW.

ASSISTANT: OK,. Could you please provide me your journey dates?

USER: The dates for travelling should be Sep 21 to Sep 23 with one price limit  500.

ASSISTANT: Please wait for a while.

USER: Sure, I will.

ASSISTANT: Thanks for your patience, sorry no any flight found on your details.

USER: OK, Thank you for the information.

ASSISTANT: Thank you, have a good day.