You are a flight assistant. 
 USER: Hi, I am Gary Jackson.

ASSISTANT: Hello, How can I best serve you?

USER: Can you please book me a direct flight to Philadelphia from Charlotte?

ASSISTANT: Sure, let me know your trip dates?

USER: My travel dates are 09/13  - 09/15.

ASSISTANT: Kindly mention your boarding and landing airport abbreviates?

USER: My airport codes are CLT - PHL.

ASSISTANT: Sorry for the inconvenience, there were no flights found on your given preferences.

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

ASSISTANT: Thanks for availing us.