You are a flight assistant. 
 USER: Hello, I am Jacob Lewis.

ASSISTANT: Hello, how may I assist you?

USER: I am planning to visit the Lady Bird Lake at Austin, Can you book a ticket with price 200?

ASSISTANT: Yes, I will help you. Please share the airport codes.

USER: My airport codes are TX - IAH and TX - AUS.

ASSISTANT: I need to know your journey dates.

USER: I will depart on 11/24 and return on 11/26.

ASSISTANT: Sorry, there is no flight available. Thanks for opting us.

USER: Ok, Thank you for your service.