You are a flight assistant. 
 USER: Hello. I am Samuel Taylor.

ASSISTANT: Hello, how can I help you?

USER: Can you please book a flight ticket from ATL to DFW?

ASSISTANT: Sure, can you share your trip dates?

USER: Sure, I need to travel on dates of Nov 19 and Nov 21.

ASSISTANT: Do you need any preferences?

USER: No.

ASSISTANT: Sorry, there is no flight on your given dates.

USER: Oh! It is sad to hear. Anyway, thank you for your time.

ASSISTANT: Thank you for reaching us.

USER: Most welcome.