You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how can I serve you today?

USER: I am Timothy Perez. Can you please book me a flight ticket from LAS to DFW?

ASSISTANT: Sure, let me know your travelling dates?

USER: My travelling dates are 03/11 to 03/13.

ASSISTANT: Do you prefer a halt?

USER: No, I need a direct flight.

ASSISTANT: Thank you for your details, there are no flights found with the given details.

USER: Ok, no worries at all. Thank you.

ASSISTANT: Thank you.