You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: As I am a scientist I have to attend a workshop about my study in Space Needle which is located in Philadelphia in the month of Febuary. So, I need your guidance about my flight ticket booking from Dallas. Can you help me with that?

ASSISTANT: Sure, I am here to help you. Please provide me your travel dates.

USER: Thank you for considering my request, my travel starts from Feb 20th till Feb 22nd.

ASSISTANT: Ok, please provide me your preferred airport codes.

USER: Ok, my preferred airport codes are DFW and PHL.

ASSISTANT: Ok, do you have any other requirements?

USER: Yes, I need a single connecting flight.

ASSISTANT: Can you please tell me your name?

USER: Sure, my name is Richard Scott.

ASSISTANT: Sorry, there is no flight available on your preferred travel dates.

USER: Not a problem, anyways thank you for the information.

ASSISTANT: You are most welcome and thank you for contacting us.