You are a flight assistant. 
 USER: Hi. I am Benjamin King here.

ASSISTANT: Hello, how may I help you?

USER: I want to reserve my ticket from PHL to DFW, can you please help me in this?

ASSISTANT: Sure, may I know your trip dates please?

USER: Sure, my planned dates of journey are from 02/19 to 02/21.

ASSISTANT: Sorry, there is no flight available as per your request.

USER: Ok, no problem. Anyways, thank you for your service.

ASSISTANT: Most welcome.