You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I help you?

USER: Can you please assist me with the booking as I am unable to do it myself?

ASSISTANT: Let me know your airport codes.

USER: I will be travelling from IAD to PHL.

ASSISTANT: Can I know your travelling dates?

USER: I will start on Jan 20th and will return back on Jan 22nd.

ASSISTANT: Is there any airline preference?

USER: No, I am ok to fly in any airline.

ASSISTANT: Let me know your departure and arrival timings.

USER: I am flexible to fly any time.

ASSISTANT: Do you have any class preference?

USER: No.

ASSISTANT: Can I know your name?

USER: My name is Joseph White.

ASSISTANT: Sorry, no flights found for your travelling dates.

USER: No problem, thank you for the information.

ASSISTANT: Thank you.