You are a flight assistant. 
 USER: Hi.

ASSISTANT: Hello. How can I help you?

USER: I am Donald Roberts want to attend a workshop at Philadelphia, can you book a ticket within the fare of 500?

ASSISTANT: Sure, may I know your journey dates please?

USER: Sure, I want travel on 09/11 and intend to return on 09/13.

ASSISTANT: Please provide me your airport codes.

USER: Ok, I want to depart from my nearest airport code ORD and land on PHL.

ASSISTANT: Please wait for a minute. I will check for the availability of flights.

USER: Sure, I will wait for your response.

ASSISTANT: I found a flight in Hawaiian airlines with price 100. Shall I book the ticket?

USER: Yes, I am ok with that airline. You can proceed with my booking.

ASSISTANT: Your ticket is confirmed and the flight number is 1001.

USER: Thank you for your service.

ASSISTANT: Thank you.