Some downloaded users.xml files are tailored for older versions (e.g., v2.8.0) and might not work on the latest, current version of the game.
You don't necessarily need to "download" a new file from the internet (which can be risky and lead to malware). Your phone already has this file if the game is installed. Location of the file: Shadow Fight 2 Users.xml File Download
It tracks player Level , Experience , and Stamina (energy). Some downloaded users