Hi ArmandoFava,
Thanks for writing and we understood your issue that ntoskrnl is not updating to latest version after installing the patch updates.
Usually Its not available to update a single system file. If want to update system file, please install the latest monthly update April 8, 2022—KB5012670 (Monthly Rollup) through Windows Update Catalog.
https://www.catalog.update.microsoft.com/Search.aspx?q=KB5012670%20
Please feel free to reach out if any questions.
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