There are multiple ways that Tamper Protection can be disabled or even weakened. Global Settings can be overridden by per-Policy settings, which can be overridden by per-Agent settings. To determine which combination of settings may be interfering with Tamper Protection:
Log in to the Console and navigate to /support.php > Advanced Configuration:
Verify Enable Agent Uninstall is unchecked.
Verify Disable Tamper Protection is unchecked.
Open a command prompt or use Terminal to issue the relevant commands to check for weakened Tamper Protection: