You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I assist you?

USER: Please help me out in booking the ticket from DFW to LAX. My trip dates will be 06/17 to 06/19.

ASSISTANT: Sure, I am here to help you with that. May I know your travelling dates to proceed further? Ok, please wait.

USER: Please book me a ticket with above mentioned details.

ASSISTANT: Ok. Sorry for the inconvenience, there are no flights on your route as per your travelling details.

USER: That's ok, anyways thank you.

ASSISTANT: May I know your name please?

USER: Sarah Robinson is my name.

ASSISTANT: Thank you for approaching us.