You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello.

USER: I am Donald Brown.

ASSISTANT: How can I help you Donald Brown?

USER: I have an interview at Philadelphia on 09/27, so can you please help me with booking a direct flight?

ASSISTANT: Sure, we are here to make your journey easy.

USER: Thank you.

ASSISTANT: Which airport did you prefer to land at Philadelphia?

USER: I will prefer to land at Philadelphia, PA-PHL.

ASSISTANT: When are planning to return on?

USER: I need to go 09/26.

ASSISTANT: Please share your take off airport code?

USER: I will catch my flight from DEN airport because it is near to me.

ASSISTANT: Thank you for your details.

USER: Please provide me a return ticket also on 09/28.

ASSISTANT: There are no direct flights available with the given travelling dates.

USER: Ok, no issues. Thank you.

ASSISTANT: Thank you.