You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello. How may I help you out?

USER: My name is Robert Jackson, I want to book a direct flight to meet my uncle, can you help me with booking a normal cost flight?

ASSISTANT: Sure, I will help you in booking the ticket. May I know your travelling dates please?

USER: My travelling dates are June 20 and June 22.

ASSISTANT: Can I know your airport codes please?

USER: I will fly from OAK to reach PHL.

ASSISTANT: Do you need any specifications?

USER: My return time is evening.

ASSISTANT: Sorry, there are no flights found.

USER: Ok, no problem.

ASSISTANT: Thank you for reaching us.

USER: Thank you.