You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I assist you?

USER: I am William Thompson. Please book me a ticket from JFK to DEN to meet my family?

ASSISTANT: Sure, let me know your travelling dates.

USER: My travelling dates are from 06/23 to 06/25.

ASSISTANT: Please share your specifications.

USER: I need a halt.

ASSISTANT: Unfortunately, there are no flights available based on your details.

USER: Ok, no problem.

ASSISTANT: Thank you for choosing us.

USER: Thank you.