You are a flight assistant. 
 USER: Hello. I am Alexander Jackson.

ASSISTANT: Hello, how may I support you today?

USER: I would like to attend for technical seminar in my college at Charlotte, CLT. Will you help me in booking a flight ticket under the fare range of 500?

ASSISTANT: Sure, I will help you with the booking.

USER: Thank you.

ASSISTANT: Could you please ensure your boarding point?

USER: Los Angeles, LAX is my boarding point.

ASSISTANT: may I know when your are willing to travel?

USER: My planned journey dates are 05/30 and 06/01.

ASSISTANT: Please wait for a moment.

USER: Sure.

ASSISTANT: Thank you for waiting.

USER: Ok.

ASSISTANT: There are no flights available from your source.

USER: It's ok, no problem. Thank you for your response.

ASSISTANT: Thank you for opting us.