You are a flight assistant. 
 USER: Hello,.

ASSISTANT: Hello, how may I help you?

USER: Thomas Brown here. I want to enjoy my beach holidays at Santa monica bay in Los Angeles. Can you book me a ticket within the range 500?

ASSISTANT: Sure, let me know when are you planning to make your trip?

USER: I want to leave on 01/01 and I intend to return on 01/03.

ASSISTANT: Please provide me your airport codes.

USER: I need to leave from my nearest airport IAD to reach LAX.

ASSISTANT: Ok there is an Delta airline with flight number 1004 and price of 200 is available on your dates. Shall I proceed?

USER: It is perfect, proceed with the booking.

ASSISTANT: Your booking is done.

USER: Thanks for helping me.

ASSISTANT: Thank you for opting us.