Have you verified the status page under Services → SMART → Info (type: All) whether the tests actually ran? Take a look at the Self-test logs section in the output. Or directly from the console by running 'smartctl -a /dev/nvme0'. Keep in mind that SMART test results aren't logged in the backend, so you'll need to check them manually as mentioned above. They also can't be monitored directly from cron jobs; for that, you'll likely need to set up Monit or a similar monitoring tool.
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