You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello, how can I assist you?

USER: Dorothy Lee here. I want you to book me a ticket from ATL to LGA, can you please help me?

ASSISTANT: Sure, may I know your planned dates to travel?

USER: My travel dates are 02/13 and 02/15.

ASSISTANT: Sorry for the inconvenience, there is no flight available on your requested dates.

USER: That's ok, thank you for your service.

ASSISTANT: Thank you for contacting us.