Hello,
It is not normal for the System item under Power & battery to occupy 91% of your device's resources. This could indicate a problem with your device's power management settings or a software issue.
I recommend checking for any updates ( Start > Settings > Windows Update) or running a virus scan to rule out any software issues. Please refer to this link:
If the problem persists, you may need to contact your device manufacturer for further assistance.
Hope this helps.
Best Regards,
Hania Lian
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