You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I am Jason King. I want to meet my parents to discuss about my higher studies at Philadelphia, PA-PHL. Can you please help me with reserving a flight ticket?

ASSISTANT: Sure, may I know your travelling dates?

USER: Sure, I want to start my journey on 07/29 and end my journey on 07/31.

ASSISTANT: Ok, let me know your source airport code?

USER: I intend to board from Las Vegas, NV-LAS.

ASSISTANT: Please wait a moment to check flight availability.

USER: Sure.

ASSISTANT: Sorry, there are no flights found on given schedule.

USER: No problem, thank you for your the information.

ASSISTANT: Thank you for reaching us.