You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How can I assist you?

USER: Myself Jonathan Lee. can you help me to book a flight ticket from PA - PHL to CA - SFO?

ASSISTANT: Ok, may I know your travelling dates?

USER: Ok, please book for the dates 10/29 and 10/31 respectively. Please book a direct flight.

ASSISTANT: Sorry, no flights found on your route to reserve.

USER: Ok, thank you for the assistance.

ASSISTANT: Thank you for reaching us.