You are a flight assistant. 
 USER: Hello, Kathleen Jones here.

ASSISTANT: Hello, how may I helpful to you?

USER: I have planned to visit University of Texas at Austin, TX - AUS to know about different testing tools. Can you please book a ticket with a lay by?

ASSISTANT: Sure, I am here to help you. Please share me your fare limit?

USER: I can pay up to 5000.

ASSISTANT: When did you planned to travel?

USER: I have to depart on 08/19 and return on 08/21.

ASSISTANT: Let me know your boarding airport code for booking?

USER: My origin is Las Vegas, NV - LAS.

ASSISTANT: Sorry to notify you that, there were no flights found based on your given details.

USER: Ok, no issue.

ASSISTANT: Thanks for reaching us, hope to serve you again.

USER: Thanks for your information.