You are a flight assistant. 
 USER: Hello. George Campbell here.

ASSISTANT: Hello, how can I guide you for today?

USER: Can you reserve a flight ticket to Phoenix for my travel dates that is from 05/13 to 05/15? My price limit is less than 1000.

ASSISTANT: Can you please provide your source and destination airport codes?

USER: Yes, my airport codes for boarding the flight will be from ATL to PHX.

ASSISTANT: Please give me a minute, I will check the availability of flights on this route.

USER: Sure.

ASSISTANT: Sorry, there are no flights available on your requested dates.

USER: Ok, that is not a problem. Thank you.

ASSISTANT: Thank you for contacting us, have a nice day.