@rr-4098 Thanks for posting in our Q&A.
To clarify this issue, we appreciate your help to collect some information:
1.Please make sure that the setting "Mark devices with no compliance policy assigned as" is set to "compliant" under Devices > Compliance policies >Compliance policy settings in intune portal.
2.Please access intune portal and click on a not compliant device > Device compliance > select the not compliant policy > find the specific setting that leads the device not compliant.
https://learn.microsoft.com/en-us/mem/intune/protect/compliance-policy-monitor#device-details
If there is anything update, feel free to let us know.
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