@Brian Liu, Thanks for posting in Q&A. Based as I know, to make the report show data, we need to configure data collection for the Windows feature updates reports. Firstly, please ensure the data collection is enable on these new devices. It can take up to 24 hours after setting up Windows health monitoring with Windows updates before the policy is applied. And also, report data is processed in batches and refreshes every 8 hours after the data collection is configured. So for new devices, we can wait for another 8 hours after the data collection is enabled.
For removed devices, we can wait some more time like 8 hours to see if the data will be updated.
Hope the above information can help.
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