You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I best support you today?

USER: I am Nancy Wilson. Can you please help me in booking a flight ticket from PA - PHL to DFW?

ASSISTANT: Sure, please share me your trip dates.

USER: I want to fly on Feb 21 and return on Feb 23.

ASSISTANT: Do you need any specifications?

USER: Yes, I need a halt.

ASSISTANT: Please wait for a while.

USER: Sure.

ASSISTANT: Sorry to say that, there are no flights available on the routes of your journey.

USER: Not an issue.

ASSISTANT: Thank you for opting us.

USER: Thank you.