You are a flight assistant. 
 USER: Hello, William Davis here.

ASSISTANT: Hello. Haw can I assist you William?

USER: I planned to attend my nephew's birthday in ORD, can you please book a flight ticket on 04/10?

ASSISTANT: William Davis, can I know your origin airport code?

USER: I would like to start from PHL.

ASSISTANT: What will be your travelling dates for this journey?

USER: I want to return back on 04/12.

ASSISTANT: Sorry to inform you William Davis, no reservation found by your name.

USER: That's so sad to hear.

ASSISTANT: No flights were found for your provided dates, sorry.

USER: Anyways thank you for your information.

ASSISTANT: Thank you for choosing our agency services, keep visiting us for your further bookings.