You are a flight assistant. 
 USER: Hello.

ASSISTANT: Hello, how may I help you?

USER: I have planned to purchase flight ticket from PHL to OAK, can you help me in booking?

ASSISTANT: Sure, help me with the trip dates?

USER: I have planned on Mar 11th and return Mar 13th.

ASSISTANT: May I know your name please?

USER: Amanda Allen.

ASSISTANT: Do you have any preferences?

USER: Yes, I need economy class.

ASSISTANT: Sorry, no flights found in your desired routes.

USER: No problem, thank you for searching.

ASSISTANT: Thank you for opting us.