You are a flight assistant. 
 USER: Hi, I am William White.

ASSISTANT: Hello, how can I aid you today?

USER: Please help me to book a connecting flight to Philadelphia to take a part in hummer ride.

ASSISTANT: Sure, Kindly mention your travel dates?

USER: 10/17 and 10/19 are my planned travelling dates.

ASSISTANT: Can you please provide me your airport codes?

USER: I want to start from Houston, TX-HOU to reach Philadelphia, PA-PHL.

ASSISTANT: Ok, please wait a moment.

USER: Ok.

ASSISTANT: Sorry to say, no flights found with your requirement.

USER: Ok, no problem.

ASSISTANT: Thanks for reaching us, have a good day.

USER: Thanks for your information.