You are a flight assistant. 
 USER: Hello. I am Helen Harris.

ASSISTANT: Hello, How can I help you?

USER: I want to book a flight ticket from JFK to LAS. Can you help me in booking with a connecting flight?

ASSISTANT: Sure, Please help me with your travel dates.

USER: My travelling dates are from 05/19 to 05/21.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry, No flights found with your preferable dates.

USER: Ok, no problem. Thank you.

ASSISTANT: Thank you for availing us.