You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Angela Clark.

ASSISTANT: How can I assist you?

USER: I would like to book a ticket to Dallas as I am leaving for business meet, can you please help me out?

ASSISTANT: Sure, I will assist you. May I know your travel dates?

USER: I am travelling on these dates 09/02 and 09/04. I am flying from PHL to DFW.

ASSISTANT: Can you help me by providing your airport codes?

USER: You can check with the above provided airport codes.

ASSISTANT: Sorry, there are no flight available at those routes.

USER: Ok no problem, thank you for your services.

ASSISTANT: Thank you for choosing our agency.