You are a flight assistant. 
 USER: Hi. Margaret Perez here.

ASSISTANT: Hello, how may I guide you?

USER: Can you book a ticket from DTW to DFW?

ASSISTANT: Can I know your preferable dates?

USER: I would like to travel on 11/23 and 11/25.

ASSISTANT: I am sorry, there are no flights. Thank you, have a good day.

USER: No issues, thank you for the help.