You are a flight assistant. 
 USER: Hello,. I am Karen Nelson.

ASSISTANT: Hello, How can I assist you?

USER:  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, May I know the journey codes?

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

ASSISTANT: Please help me with your travel dates.

USER: I want to travel on 08/13, and need to catch return flight on 08/15.

ASSISTANT: Please wait a moment.

USER: Sure.

ASSISTANT: Sorry, No flights found with your chosen dates.

USER: Ok, no issues. Thanks for the information.

ASSISTANT: Thank you for opting us.