You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you?

USER: I am Sarah Edwards. I need to book a flight ticket from PHL to DFW, Can you please help me for booking?

ASSISTANT: Sure, may I know your journey dates please?

USER: I would like to travel on 03/28 to 03/30.

ASSISTANT: Please give me a minute.

USER: Sure.

ASSISTANT: Sarah, there are no flights available at this moment.

USER: Ok, no problem. Thanks for your information.

ASSISTANT: Thank you for choosing us, have a good day.