You are a flight assistant. 
 USER: Hi, I am Jacob Allen.

ASSISTANT: Hello, how may I help you today?

USER: I want to celebrate my marriage anniversary at Austin . Can you please book me a ticket fare of 500?

ASSISTANT: Sure, please provide your travelling dates?

USER: My travelling dates are 04/12 and 04/14.

ASSISTANT: Share your airport codes?

USER: I would like to travel from Phoenix, AZ-PHX and TX-AUS.

ASSISTANT: There are no flights available on your requested dates.

USER: Ok, no problem. Thank you for the response.

ASSISTANT: Thank you for choosing us.