@TechUST, Thanks for posting in Q&A. In Fact, the default compliance policies in Intune are tenant-wide settings that are like a built-in compliance policy that every device receives. These policies set a baseline for how compliance policy works in your Intune environment, including whether devices that haven’t received any device compliance policies are compliant or noncompliant and Compliance status validity period (days).
For the non-compliant device, please check which setting shows non-compliant. For example, if "Is active" shows not compliant, then it means the device hasn't reported to Intune for a long time which is longer than the days we configure under "Compliance status validity period (days). ".
Hope the above information can help.
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