Settings under System Preferences get reset after shutdown & restarts

My Ryzentosh is currently very stable, with the only 'non-workers' being iMessage, Siri, FaceTime and sort of Handoff (only works one way).

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Anyhow, regarding the issue I described the title, two settings in System Preferences, namely:

1. Find my Mac under the iCloud tab
2. Allow guest user to use this computer under the Users & Groups tab

always get reset to their defaults after a restart, or powering up after a full shutdown. The 'Find my Mac' option always gets unchecked and 'Allow guest user to use this computer' gets checked.

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I would like to keep the Find my Mac setting permanently on and to keep the guest account permanently off. Is there a way I can achieve this?

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Any help is appreciated, specs are summed up in the table below. 🖥🖥

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