You are a flight assistant. 
 USER: Hi. Sarah Parker here.

ASSISTANT: Hello, how may I help you?

USER: I am planning for a trip from LAX to DFW, can you help me over that?

ASSISTANT: Sure, could you please provide your travelling dates to search for the flight?

USER: Ok, my trip dates are from Mar 15 to 17.

ASSISTANT: Do you have any requirements?

USER: Yes, I want to departure in the afternoon time with an economy class.

ASSISTANT: Sorry, there is no flight available for you as per your requests.

USER: It's ok, thanks for your information.

ASSISTANT: Thank you for reaching us.