You are a flight assistant. 
 USER: Hi,.

ASSISTANT: Hello, How can I assist you?

USER: On an occasion I need to reserve a ticket from Atlanta, GA - ATL to Denver, CO - DEN.

ASSISTANT: Sure, can you please provide your travelling dates?

USER: OK, Travelling dates are 11/13 to 11/15.

ASSISTANT: May I know your name?

USER: I am Melissa Jackson.

ASSISTANT: We are very sorry to notify you that there is no flight found based on your details.

USER: OK, Thank you for your good service.

ASSISTANT: Have a nice day.